📘 Unit 2 - Addition | Textbook Exercise Answers
📄 Page 50 — Addition Game (Activity)
Group-1 (solved example):
| 5 4 9 3 |
| + 7 8 2 6 |
| 1 3 3 1 9 |
5493 + 7826 = 13319
Note: Group-2 and Group-3 grids are empty because students create their own 4-digit numbers by throwing a ball at the number board. Students should add their own two numbers the same way as shown in Group-1 to find their "Group Total".
📄 Page 52 — Do These
Q1. Add the following.
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Q2. Add 4789 and 2946
4789 + 2946 = 7735
Q3. Find 7645 + 5895
7645 + 5895 = 13540
🤖 AI Addition Machine (Machine adds 4728 to any number entered)
Example 1 (already solved in book): 2896 + 4728 = 7624
Note: For items 2–5, students enter a 4-digit number of their own choice and add 4728 to it using the same column method shown in the example.
📄 Page 54 — Do These (Estimation)
Q1. Estimate the sum in each case and tick (✓) the correct estimation rounded to thousands.
| S.No | Sum | Actual Value | Correct Estimation |
|---|---|---|---|
| 1 | 1686 + 3250 | 4936 | 5000 |
| 2 | 2432 + 2980 | 5412 | 5000 |
| 3 | 3480 + 5700 | 9180 | 9000 |
| 4 | 1984 + 5680 | 7664 | 8000 |
| 5 | 4830 + 987 | 5817 | 6000 |
🚲 Bicycle Cost Table Activity
Given costs — Gear bicycles: ₹7150, ₹5100, ₹8150 | Small bicycles: ₹1800, ₹2670, ₹3850
Row 1 (given example): ₹7150 + ₹1800 = ₹8950 (rounded: 7000+2000=9000)
Other valid combinations with total cost under ₹10,000 (any 3 can be used to fill rows 2, 3, 4):
₹5100 + ₹1800 = ₹6900 (rounded: 5000+2000=7000)
₹5100 + ₹2670 = ₹7770 (rounded: 5000+3000=8000)
₹5100 + ₹3850 = ₹8950 (rounded: 5000+4000=9000)
₹7150 + ₹2670 = ₹9820 (rounded: 7000+3000=10000)
₹8150 + ₹1800 = ₹9950 (rounded: 8000+2000=10000)
📄 Page 58 — Do These
Q1. A water tank supplies drinking water to two villages. They supplied 3870 liters of water to the first village and 5295 liters of water to the second village. How many liters of water in total are supplied to both villages?
Answer:
Water supplied to first village = 3870 liters
Water supplied to second village = 5295 liters
Total water supplied = 3870 + 5295 = 9165 liters
Q2. On Vanamahotshavam, in a mandal 7365 saplings were planted in schools and 2859 saplings were planted in offices. How many saplings were planted in total?
Answer:
Saplings planted in schools = 7365
Saplings planted in offices = 2859
Total saplings planted = 7365 + 2859 = 10224 saplings
📄 Page 60 — Try These
Make word problems for the following.
a) 6854 + 3521
Word Problem: Ramu has ₹6854 and Krishna has ₹3521. What is the total amount both of them have?
Answer: 6854 + 3521 = 10375
b) 5340 + 3564
Word Problem: A library has 5340 story books and 3564 comic books. How many books are there in total?
Answer: 5340 + 3564 = 8904 books
c) 4563 + 8520
Word Problem: In a factory, 4563 units were produced on Monday and 8520 units were produced on Tuesday. What is the total production?
Answer: 4563 + 8520 = 13083 units
📄 Page 64 — Try This
Q1. Fill the boxes with suitable digits.
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a) 7393 + 1365 = 8758 b) 4769 + 2587 = 7356
Q2. Find the sum by suitable regrouping.
a) 740 + 320 + 260 + 2680 = (740+260) + (320+2680) = 1000 + 3000 = 4000
b) 5986 + 2976 + 14 + 24 = (5986+14) + (2976+24) = 6000 + 3000 = 9000
c) 4893 + 894 + 106 + 107 = (4893+107) + (894+106) = 5000 + 1000 = 6000
✏️ EXERCISE - 1
Q1. Add the following.
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Q2. Observe whether the following additions are correct or not. Correct them if it is wrong.
a) 3648 + 4826 = 7464 (given) → Incorrect. Correct answer: 3648 + 4826 = 8474
b) 5017 + 3977 = 9094 (given) → Incorrect. Correct answer: 5017 + 3977 = 8994
c) 3897 + 4069 = 7856 (given) → Incorrect. Correct answer: 3897 + 4069 = 7966
Q3. Write word problems for the following additions.
a) 3268 + 5634 = ?
Word Problem: A shop sold 3268 kg of rice in the morning and 5634 kg of rice in the evening. What is the total quantity of rice sold?
Answer: 3268 + 5634 = 8902 kg
b) 6240 + 5425 = ?
Word Problem: In a stadium, there were 6240 male spectators and 5425 female spectators. What is the total number of spectators?
Answer: 6240 + 5425 = 11665
Q4. Fill in the blanks.
a) 632 + 984 = 984 + 632 (Addition can be done in any order and the sum remains the same)
b) 2735 + 2569 = 2569 + 2735
Q5. A number is 6897 more than 5478. Find that number.
Answer:
Given number = 5478
Number is more by = 6897
Required number = 5478 + 6897 = 12375
Q6. Veeraiah sold maize for ₹5397 and pearl millets for ₹3849 in a village fair. How much amount did he get?
Answer:
Amount earned on maize = ₹5397
Amount earned on pearl millets = ₹3849
Total amount earned = 5397 + 3849 = ₹9246
📄 Page 66 — Exercise-1 (continued)
Q7. Madhav produced 3985 watermelons in his field. Vijayendar produced 854 more than Madhav's. What is the number of watermelons produced by Vijayendar?
Answer:
Watermelons produced by Madhav = 3985
Watermelons more produced by Vijayendar = 854
Watermelons produced by Vijayendar = 3985 + 854 = 4839
Q8. In an electronics store, the prices of four fans are shown: Fan 1: ₹7200, Fan 2: ₹5800, Fan 3: ₹4650, Fan 4: ₹3900. Find the two fans whose total cost is ₹13,000. [ ]
Answer:
Fan 1 + Fan 2 = 7200 + 5800 = ₹13000 → Answer: A) Fan 1 and Fan 2
Q9. Which pair of numbers adds up to 400? [ ]
A) 120 + 270 = 390
B) 199 + 199 = 398
C) 150 + 190 = 340
D) 198 + 202 = 400 ✓
Answer: D) 198 and 202
📌 Project Work
This is a field activity. Students should collect their own village's population, literacy, and voter data from the Panchayat Secretary and fill it in the table, then answer the questions based on the collected data (total population = male + female; total literates + illiterates; comparison of male/female literates; and comparing total voters with total population).
📄 Page 68 — Improve Your Learning
Q1. The figure is called a Magic square because the sum of the numbers along every row, column and diagonal is the same. What are the values of ■ and ●?
| 12 | 7 | 8 |
| 5 | 9 | 13 |
| 10 (■) | 11 (●) | 6 |
Answer:
Magic sum (each row/column/diagonal) = 5 + 9 + 13 = 27
Column 1: 12 + 5 + ■ = 27 → ■ = 10
Column 2: 7 + 9 + ● = 27 → ● = 11
Check row 3: 10 + 11 + 6 = 27 ✓
Q2. A machine adds 4728 to the number that is put in. If the final output is 6000, what number was entered?
Answer:
Final output = 6000
Number added by machine = 4728
Number entered = 6000 − 4728 = 1272
Q3. Rafi has to add two numbers 354 and 462. But he adds 354 + 452 = 806. Later he identifies his mistake. What should be done to correct his mistake? ( a )
Answer:
Correct sum: 354 + 462 = 816
Rafi's wrong sum = 806 (he used 452 instead of 462, i.e., 10 less)
To correct it, he should add 10 to 806 to get 816. Answer: a) Add 10
Q4. Nagamma placed weight stones on both pans of a weighing balance (Pan A: 1530g, 2435g, 1045g; Pan B: 2000g, 3005g). If she lifts the weighing balance, which statement would be true? ( a )
Answer:
Total weight on Pan A = 1530 + 2435 + 1045 = 5010 g
Total weight on Pan B = 2000 + 3005 = 5005 g
Since Pan A (5010g) is heavier than Pan B (5005g), Pan A would go down — because of more total weight, not because of the number of stones. Answer: a) Pan A would go down
Q5. In a village there are 2525 males. The number of females is 250 more than the number of males. What is the total population of the village?
Answer:
Number of males = 2525
Number of females = 2525 + 250 = 2775
Total population = 2525 + 2775 = 5300
Q6. You are a shopkeeper. Create a receipt for three items where the total equals exactly ₹9246. One item must cost ₹5397.
Answer (sample receipt):
Item 1 = ₹5397
Item 2 = ₹2000
Item 3 = ₹1849
Total = 5397 + 2000 + 1849 = ₹9246
