Vertical or column addition We can add numbers by writing them one below the other. This is called vertical addition or column addition. Let us see a few examples. Addition of 1-digit numbers Example 4: Add 6 and 2 by writing the numbers in columns. Solution: Write the numbers under the ones place, as shown. O 6 +2 8 Addition of 2-digit numbers Example 5: Add the following by writing the numbers in columns. 23 + 32 Solution: Step 1: Add the ones. Step 2: Add the tens. TO TO 23 23 +32 +32 5 55 TO Solve these TO 41 78 +2 8 TO +2 1 14 +3 3 Addition 45 Visa_G1_Maths_TB1_V1.indb 45 9/17/2022 2:55:06 PM
Train My Brain Add the following numbers. a) 3 + 7 (Using fingers) b) 6 + 5 (Using a number line) c) 15 + 14 (Using vertical addition) 4.1 I Apply We now know how to add numbers. Let us see some real-life examples of addition of numbers. Example 6: Madhu has 5 kites and Sita has 4 kites. How many kites do they have in all? Solution: Write the numbers one below the other. Add them and write the sum as shown. O 5 +4 9 So, Madhu and Sita have 9 kites in all. Example 7: Ram had 14 marbles. Shyam gave him 15 marbles. How many Solution: marbles does Ram have altogether? TO 14 Write the numbers one below the other. Add them + 15 and write the sum as shown. So, Ram has 29 marbles altogether. 29 4.1 I Explore We have learnt how to add two 1-digit and 2-digit numbers. Let us now learn to add three 1-digit and 2-digit numbers. 46 Addition Visa_G1_Maths_TB1_V1.indb 46 9/17/2022 2:55:12 PM
Example 8: Sunita bought 2 mangoes, 3 apples and 4 bananas. How many fruits did she buy altogether? Solution: Write the numbers under the ones place and add. O 2 +3 +4 9 So, Sunita bought 9 fruits. Example 9: There are 14 students in Row 1. Row 2 has 15 students. Row 3 has 10 students. How many students are there altogether? Solution: Write the numbers one below the other. Step 1: Add the ones. Step 2: Add the tens. T O T O 14 14 + 15 + 15 + 10 + 10 9 39 So, there are 39 students altogether. Addition 47 Visa_G1_Maths_TB1_V1.indb 47 9/17/2022 2:55:16 PM
4.2: Add Two 1-digit Numbers Mentally To add numbers mentally, we must first know the correct order of numbers. Can you write the numbers from 0 to 9 in the correct order? 0 9 Let us now learn to add two 1-digit numbers mentally. How do we add numbers mentally? To add two numbers mentally, first keep the bigger number in mind. Then, count the smaller one on the fingers. If the two given Let us learn this through some examples. numbers are To add any two numbers mentally, we follow the steps the same, we given below. Look at how the numbers 2 and 5 have been added. can keep any number in mind Then, try adding 3 and 6 mentally by yourself. Fill in the and count the blanks in the table. other number on the fingers. Steps Added mentally: 2 + 5 Add mentally: 3 + 6 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 smaller number. So, keep 2 fingers open. So, keep fingers open. Step 3: Begin counting the fingers. The number after 5 is 6. The number after Start from the number Count 2 fingers as 6 is . fingers after the bigger number. and 7. Count Step 4: Write the last as , and . number as the sum of the The sum of 2 and 5 is 7. The sum of 3 and 6 is . given numbers. Now, how do we add bigger numbers mentally? 48 Addition Visa_G1_Maths_TB1_V1.indb 48 9/17/2022 2:55:20 PM
To add any two bigger numbers mentally, we follow the steps given below. Look at how the numbers 6 and 7 have been added. Then, try adding 5 and 9 mentally by yourself. Fill in the blanks in the table. Steps Added mentally: 6+7 Add mentally: 5+9 Step 1: Keep the bigger The bigger number is 7. The bigger number is number in mind. So, keep 7 in mind. . So, keep in mind. Step 2: Keep as many The smaller number is 6. The smaller number is fingers open as the smaller number. So, keep 6 fingers . So, keep open. fingers open. Step 3: Begin counting The number after 7 is 8. The number after is the fingers. Start from Count 6 fingers as 8, 9, , the number after the 10, 11, 12 and 13. . Count bigger number. fingers as , , and . Step 4: Write the last The sum of 6 and 7 is 13. The sum of 5 and 9 is number as the sum of . the given numbers. We have seen how easy it is to add two 1-digit numbers mentally. Let us now see how we can use it in our daily lives. Imagine that in a class, Team A has 5 students and Team B has 7 students. Can you find out how many students there are in all? Let us do it together. Number of students in Team A = 5 Number of students in Team B = 7 The bigger number is 7. Keep 7 in your mind. The smaller number is 5. Keep 5 fingers open. After 7, count 5 fingers as 8, 9, 10, 11 and 12. So, the total number of students in Team A and Team B is 12. Now imagine your friend, Seema has 3 milk chocolates and 6 dark chocolates. How many chocolates does she have in all? Addition 49 Visa_G1_Maths_TB1_V1.indb 49 9/17/2022 2:55:29 PM
Number of milk chocolates = 3 Number of dark chocolates = 6 The bigger number is 6. So, keep 6 in your mind. The smaller number is 3. Keep 3 fingers open. After 6, count 3 fingers as 7, 8 and 9. So, Seema has 9 chocolates in all. Reflection Time! 1) You are playing Snakes and Ladders with your friend. Your coin is now at 2. The dice thrown shows 6. Where will you place the coin now on the board? On your next turn you get 2 on the dice. Where will you place your coin now? 2) Your friend is reciting numbers from 1 to 20 as 1, 2, 4, 3, 5, 6, 8, 7, 10, 9, 11, 12, 13, 15, 14. Is he reciting the numbers in the correct order? Arrange the numbers in the correct order and recite them. Maths Munchies 5+3=8 We can add two numbers by drawing lines. Suppose we have to add 5 and 3. First draw 5 lines and then 3 lines as shown. Then, count the lines continuously. The number we get for the last line is the sum of the two given numbers. 5 + 3 = │││││ + │││ = 8 So, 5 + 3 = 8. 50 Addition Visa_G1_Maths_TB1_V1.indb 50 9/17/2022 2:55:33 PM
Connect the Dots EVS Fun How many fingers do we have in total? To find this, we ‘add’ the fingers of both the hands. Can you count the fingers in the given picture? Now, count the fingers in both your hands. English Fun Some words in the English language are also formed by adding two different words to make a single meaningful word. For example, Moon + light = Moonlight Sun + rays = Sunrays Can you write a few such words? Addition 51 Visa_G1_Maths_TB1_V1.indb 51 9/17/2022 2:55:46 PM
Drill Time 4.1: Add 1-digit and 2-digit Numbers 1) Add the following numbers using the number line. a) 3 and 3 b) 2 and 6 c) 1 and 7 d) 4 and 2 e) 3 and 4 2) Add the following numbers using the vertical or column method. a) 2 and 5 b) 3 and 6 c) 21 and 42 d) 17 and 61 e) 10 and 40 3) Word problems a) I have 2 pens and my sister has 2 pens. What is the total number of pens we have? b) Krish picked 12 sticks and Sanjay picked 20 sticks. How many sticks did they pick in all? 4.2: Add Two 1-digit Numbers Mentally 4) Add mentally a) 2 and 7 b) 1 and 3 c) 3 and 3 d) 8 and 2 e) 7 and 9 A Note to Parent Play Snakes and Ladders with your child to make him or her understand and use addition in a fun and easier way. 52 Addition Visa_G1_Maths_TB1_V1.indb 52 9/17/2022 2:55:53 PM
MATHS LAB ACTIVITY Maths Lab ActivMitAyTHMSALTHASBLAB ACTIVITY Maths Lab Activity AAimim: T:o make numbeTr obomnMMdasAkAuTeTsHHinnSSguLLmaAABBnbuAeAmrCCbbTTeIoIrVVnIIbTTdaYYlsanucseing a number balance. Maths Lab Activity Maths Lab AcMtR432S13RS214t))))e....e tqepeuqspSRA31223SRA1i:sPTWNu...rt...NTWPeitseeiiemequamaiuqd:pmoopWPToruokWTPk:usttw:seweuair:euaeri:eoraka,orktnkmktesreear,aetmkatamkuiaa:tineanieaniekcNnnonononnnuonphekunnuputunnpmtpta:me:atmm:oamtooiawiboinA312RSrhbrnbntrbiesseNTeosnw...eNTebtrae.er.e.riorseoussreNumtoeiqbsbiobmmd.pmmdrriabtaaPWTsueduel:habsaloambalibaeoukaaeiok:mldneenraforeraofnkeroctceetnbertlnrmpbcfebnhehaa.eamcuk.eaueotaeelenl.maaohmanfrrninencerubntubncatoncbeesemeemhnenurn.raptbutebdb:bmloeameooaoranprgninnnbbbrnlbduedaseecaNTesdstlcrml.earhauoeusnubnspseibbciicaimmdntelnreaelaggaeoolrmabcnnaannaokebecnnanaatefrenaunuihckytmytlombeeneahnnonb.abunnueue8nelaumrmcmra.nnmbebtnbbyauhbaeebclolrareemanee,,nnnrrusscncsaabmeebayyu.o.enob8n8mr.e.nyrtb,dbhnaseesualraouymstnsh8ocbie.nenregrsoti,hndaseeanasoynuutycm8hh.enbruemr bbaelra,nscae 1044..t1h9100sNasNi9itd9odo8ewtew88hs,s,ueu7tt7a7cacphkhk6ea6e6tthrthtw45atw5ast.to5ot4t4tho1hoo0erer3g4sN3mpmpei9ada2too2orhr3rterwtese1es18rtst,o2ouamga1tg1n7neaceadtdt12hkh2hkpep6eeelr3tlr3aah8mtcmc1w4e5a4.eaaitkikto5t52eeto4oh8no8n66..etr3th3h77empe n84an82ouurm9rm9t5es1bb110e0etrro6ssag1oonnen35735dttt2hhhepe8eoolr3tathh89m8ceeSRA4rera1te0iiketm5qepou:s8n6i:.rte53h7me en8 nutm9: 8b10eNTrosuommn5abtkeherebn 1. Work in pairs. 2. Take a number ba3lance 1055uE..E19sx1x00uEiuEppn9sx9sxlil8poigpnonl8rlg8ogorer7re7e7ea...anaa6n6n6dndd55d5fffi.i5innn4f4dddin3Eu4a3aaldlllsxl2l2pipp3anpoo1l1olsgsolsss2iisrbp1b1iellbeoe.12l2awsewsna3aw3iydyb1ass44lytfteoosi552nmmwtod66aaak3km7ae7yelannsl848ukuptmemo99o5bnbe1mse1u00rrsm6bbiaobobknnel7eded341r314ssnbwoo8ofufna88mdy98s8sb34oet1..f0or180bmsPNuoi9usdaonitknewd48geass,unto7.acuofhkmn86etbohtenw5aretobt4shooidern3edmposa2ofrorttfes1 55). 6) 66..ReRRpeeeppaeetaattththheeeaaaccttiiivv1vi0ititytyy9ffoofrroo8rotthohete7rhr nenuru6mmnbub5eemrrssb..4ers3. 2 1 38 4 1 2 3 4 5 6 7 8 9 10 13 6. Repeat the activity for other numbers. 5. Explore and find a1ll po using . 6. Repeat the activity for other numbers. 34 34 53 10 9 8 7 6 5 4 3 2 1 Visa_G1_Maths_TB1_V1.indb 53 9/17/2022 2:56:00 PM
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 Visa_G1_Maths_TB1_V1.indb 54 54 9/17/2022 2:56:05 PM
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