Solution: Two numbers and their sum are given. We can use any situation to frame the story sum. Step 1: Think of a situation. Step 2: Here, let us take the number of different fruits such as oranges and apples in a basket. Write the story in your words. There were 32 oranges and 22 apples in a fruit basket. How many fruits were there in all? Maths Munchies Trick to add 3-digit numbers quickly: 355 + 152 Step 1: 355 + 152 can be written as 350 + 5 + 150 + 2 In this step, 355 is split into 350 and 5 and 152 into 150 and 2 Step 2: 350 + 150 = 500 5+2=7 500 + 7 = 507 So, 355 + 152 = 507. Connect the Dots EVS Fun Count the total number of fingers and toes you have. Also count the same for the other members of your family. Write the total number of fingers and toes that you have counted. Addition 45 Visa_G2_Maths_TB1_V1.indb 45 19-09-2022 14:31:01
English Fun Let us read a funny poem about addition. I got a new dog, Addition’s his name, He lives in the kitchen, eating’s his game! He weighed in at 4 pounds, but added 4 more, 8 pounds was the sum, he couldn’t squeeze out the door... 8 pounds? Not big! So he added 8 more, The sum was 16, he was growing galore! 16’s enough! I yelled, ‘Don’t get bigger’! 16 more pounds was too heavy to figure! Now Addition’s so big, it’s just a sad fact, I’ll need dog, Addition, to learn to subtract. Drill Time 4.1: Add 2-digit and 3-digit Numbers 1) Add 2-digit numbers with regrouping. a) 77 + 13 b) 26 + 35 c) 19 + 35 d) 49 + 12 e) 55 + 25 2) Add 3-digit numbers without regrouping. a) 166 + 111 b) 612 + 352 c) 181 + 315 d) 490 + 100 e) 812 + 121 3) Word problems a) Farah has 11 balloons and her friend has 29 balloons. How many balloons do they have in all? b) A khil had 120 pens in one box and 121 pens in another box. How many pens did he have in all? A Note to Parent Take your child to the supermarket. Ask them to pick up three things of their choice and find the total cost of the items. 46 Addition Visa_G2_Maths_TB1_V1.indb 46 19-09-2022 14:31:02
5 Subtraction I Will Learn subtracting 2-digit and 3-digit numbers About properties of subtraction using Mental Maths techniques for subtraction 5.1: Subtract 2-digit and 3-digit Numbers I Think David got 83 candies from his parents on his birthday. He gave 27 candies to his friend Neha. How can David find the number of candies left with him without counting? 5.1 I Recall In Grade 1, we learnt to subtract using a number line and by counting. We have also learnt subtraction using the place value chart. Let us solve the following to recall the concept of subtraction. 47 Visa_G2_Maths_TB1_V1.indb 47 19-09-2022 14:31:03
Count, write and subtract the numbers in the boxes. a) b) c) d) Subtraction 48 19-09-2022 14:31:07 Visa_G2_Maths_TB1_V1.indb 48
5.1 I Remember and Understand Subtraction of 2-digit numbers with regrouping Place values of digits in 2-digit numbers are tens and While subtracting, ones. Sometimes, subtracting 2-digit numbers needs always start from regrouping. Let us see some examples. the ones place. Example 1: Subtract 48 from 56. Solution: To subtract, follow these steps: Steps Solved Solve these Step 1: Write the numbers according to their TO TO places. Subtract the digits in the ones place. But, we cannot subtract 8 from 6. So, we 56 4 4 have to regroup the tens. –4 8 –3 8 5 tens = 4 tens + 1 ten. We know that 1 ten = 10 ones. Step 2: Add 1 ten to the ones place. So, TO TO it becomes 16 ones. Also, subtract 1 ten 4 16 from the tens place (that is, 5 – 1 = 4). Now, 56 9 8 subtract 8 from 16. That is, 16 – 8 = 8. Write –4 8 –3 9 the difference in the ones place. (Note: You cannot subtract from zero. You must borrow 8 TO from the next place instead. For example, for subtracting 27 from 40, you cannot subtract TO 8 6 7 from 0. Hence, you borrow 1 from 4 (the 4 16 –2 7 tens place of 40) to make 0 as 10, which 56 makes 4 become 3. –4 8 08 Step 3: Subtract the digits in the tens place. That is, 4 – 4 = 0. Write the difference in the tens place. So, 56 – 48 = 8. Subtraction 49 Visa_G2_Maths_TB1_V1.indb 49 19-09-2022 14:31:07
Subtract 3-digit numbers without regrouping Let us understand how to subtract 3-digit numbers through an example. Example 2: Subtract 141 from 943. Solution: To subtract the given numbers, follow these steps: Steps Solved Solve these Step 1: Arrange the numbers HTO HTO according to their place values. 943 784 –1 4 1 –3 3 2 HTO HTO 496 Step 2: Subtract the digits in the 943 –2 6 2 ones place. Write the difference in – 1 4 1 the ones place. That is, 3 – 1 = 2. 2 HTO HTO 636 Step 3: Subtract the digits in the 943 –1 3 0 tens place. Write the difference in –1 4 1 the tens place. That is, 4 – 4 = 0. 02 Step 4: Subtract the digits in H TO HTO the hundreds place. Write the 9 43 846 difference in the hundreds place. –1 41 –4 2 0 That is, 9 − 1= 8. 8 02 So, 943 – 141 = 802. Properties of subtraction 1) Zero property: When we subtract 0 from a number, the difference is the number itself. For example, 12 – 0 = 12 50 Subtraction Visa_G2_Maths_TB1_V1.indb 50 19-09-2022 14:31:07
2) Before numbers property: When we subtract 1 from a number, we get the number that is just before it. For example, 35 – 1 = 34 3) Subtracting a number from itself: When we subtract a number from itself, the difference is 0. For example, 35 – 35 = 0 Train My Brain a) Subtract 0 from 12. b) Find the difference between 50 and 1. c) What is the difference when a number is subtracted from itself? 5.1 I Apply We use the concept of subtraction to solve some real-life situations. Let us see a few examples. Example 3: A class of 390 students is divided in red and blue groups. Among them, 150 students are in the red group. How many students are in the blue group? Solution: Number of students in the class = 390 HTO Number of students in red group = 150 39 0 Number of students in blue group = 390 – 150 −15 0 So, there are 240 students in the blue group. 2 4 0 Example 4: There are 52 candies in a jar. Children ate 37 of TO them. How many candies are left in the jar? 4 12 52 Solution: Number of candies in a jar = 52 Number of candies eaten by children = 37 Number of candies left in the jar = 52 – 37 −3 7 So, there are 15 candies left in the jar. 15 Subtraction 51 Visa_G2_Maths_TB1_V1.indb 51 19-09-2022 14:31:08
5.1 I Explore Let us now learn to frame a story sum based on subtraction. Example 5: Given 163 −120 = 43, frame a story sum. Solution: Two numbers and their difference are given. We can use a situation to frame the story sum. Step 1: Think of a situation. For example, Shyam takes some chocolates to school on his birthday. Since it is subtraction, these chocolates should be given away. Step 2: Write the story in your words. Shyam takes 163 chocolates to school on his birthday. He shares 120 chocolates among his classmates. How many chocolates are left with him? 52 Subtraction Visa_G2_Maths_TB1_V1.indb 52 19-09-2022 14:31:08
5.2: Subtract Two 1-digit Numbers Mentally We have already learnt the correct order of numbers and how to subtract numbers. But how do we subtract numbers mentally? To subtract numbers mentally, we need to remember the correct order of numbers. Let us understand how to subtract two 1-digit numbers mentally through this example. Suppose we want to subtract 2 from 5 mentally. To do so, we follow these steps. Steps Subtracting 2 from 5 Subtract 4 from 9 Step 1: Keep the bigger The bigger number is 5. The bigger number is _____. number in mind. So, keep 5 in mind. So, keep _______ in mind. Step 2: Keep as many The smaller number is 2. The smaller number is fingers open as the So, keep 2 fingers open. _____. So, keep _______ smaller number. fingers open. Step 3: Begin counting The number before The number before ___ backwards from the 5 is 4. Count 2 fingers is ___. Count ___ fingers bigger number. Fold backwards as 4 and 3. backwards as ___, ___, as many fingers as the ___ and ____. smaller number. Step 4: Write the number The difference between The difference between 9 obtained in step 3 as the 5 and 2 is 5 – 2 = 3. and 4 is 9 – 4 = ___. difference between the given numbers. We have seen how easy it is to subtract 1-digit numbers mentally. If the two given It is important to use the mental subtraction of numbers in real-life numbers are situations. Let us look at a few examples of how we can do so. the same, their difference is zero. Your friend Meena has 7 chocolates with her. She gave 3 of them to her sister. How many chocolates are left with Meena? Number of chocolates Meena has = 7 Subtraction 53 Visa_G2_Maths_TB1_V1.indb 53 19-09-2022 14:31:09
Number of chocolates Meena gave to her sister = 3 The bigger number is 7. The smaller number is 3. We keep the bigger number in mind and count the smaller number on our fingers. So, we keep 7 in mind and count 3 on our fingers. When we subtract, we count backwards. So, starting after 7 we count 3 fingers backwards as 6, 5 and 4. Therefore, Meena has 4 chocolates left with her. Sameer is on an 8-day- long vacation in Shimla with his family. He has spent 5 days there. How many days are left of his vacation? Reflection Time! 1) We have seen some examples of how we can use mental subtraction in real-life situations. Can you think of any situation in which you had to subtract numbers mentally? How did you do it? 2) What day is it today? Can you calculate mentally how many days are left till the weekend? Maths Munchies Subtraction of 2-digit numbers from 100: 1 0 0 − 8 6 4 Consider the example 100 – 86. In this example, we have subtracted from 9 from 10 8 from 9 and then 6 from 10 which results in 14. This trick helps in faster = 1 calculations. 54 Subtraction Visa_G2_Maths_TB1_V1.indb 54 19-09-2022 14:31:10
Connect the Dots English Fun Let us read a poem about subtraction. Here we go subtracting numbers, To find the difference Subtracting numbers, subtracting Next you take away a part, numbers Away a part, away a part, Here we go subtracting numbers, Next you take away a part, To find the difference To find the difference First you start with the whole, You have found the other part, With the whole, with the whole, The other part, the other part, First you start with the whole, You have found the other part, That is the difference. EVS Fun You have invited 15 people. 6 of them are your friends. Also, there is 1 uncle, 1 aunt and 3 cousins. Your parents and grandparents are also there. If we separate all the extended family members, how many guests will remain? Subtraction 55 Visa_G2_Maths_TB1_V1.indb 55 19-09-2022 14:31:11
Drill Time 5.1: Subtract 2-digit and 3-digit Numbers 1) Subtract 2-digit numbers with regrouping. a) 25 – 18 b) 37 – 29 c) 48 – 19 d) 56 – 27 e) 90 – 25 2) Subtract 3-digit numbers without regrouping. a) 356 – 256 b) 197 – 106 c) 786 – 122 d) 476 – 111 e) 854 – 221 3) Word problems a) Vivaan has 33 cups in a box. He removed 17 of them and placed on the table. How many cups are left in the box? b) Baiju has 142 marbles with him in a basket. Out of these, he removed 100. How many marbles are left in the basket? 5.2: Subtract Two 1-digit Numbers Mentally 4) Subtract the following mentally. a) 3 from 9 b) 2 from 7 c) 2 from 4 d) 7 from 8 e) 1 from 2 5) Word problems a) Sana drew 8 balloons out of which she coloured 6 red and the rest blue. How many balloons were coloured blue? b) R ohan made a bunch of 5 flowers out of which 1 flower fell down from his hand. How many flowers are left in his hand? A Note to Parent Give your child some toffees. Now play as follows: a) A sk for 0 toffees. Then, ask the number of toffees left. b) A sk them to give you 1 toffee. Then, ask to count the number of toffees left. c) Ask them to give you different number of toffees and ask to count the number of toffees left. 56 Subtraction Visa_G2_Maths_TB1_V1.indb 56 19-09-2022 14:31:11
MATHS LAB Aim: To form 3-digit numbers and find their sum Requirement: Deck of cards (1 to 5) Steps : 1. Pair up with your friend. 2. Take five cards numbered 1 to 5. With the help of your teacher, shuffle them and place them on 2 3 5the table upside down. 3. Now, pick any three cards and make a 3-digit number with those. For example, you pick the cards 5 2 3numbered 2, 3 and 5, and make the number 235. 4. Ask your friend to make another 3-digit number using the same cards you picked. So, your friend can make the number 523. 5. Now, both of you have a number each. Add your numbers together and find the sum. 6. Play a few more rounds by repeating steps 2 to 4 and complete the table given below. First number Record Table Sum 1) 235 Second number 758 2) 523 3) 4) 5) 6) Visa_G2_Maths_TB1_V1.indb 57 57 19-09-2022 14:31:12
Student Reflection Come to this page after you complete a chapter. Choose the smiley that shows how well you have understood the chapter. Shapes Patterns Very clear Clear Somewhat clear Not clear at all Very clear Clear Somewhat clear Not clear at all Numbers Addition Very clear Clear Somewhat clear Not clear at all Very clear Clear Somewhat clear Not clear at all Subtraction Very clear Clear Somewhat clear Not clear at all 58 19-09-2022 14:31:13 Visa_G2_Maths_TB1_V1.indb 58
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