📘 Class 5 Maths Magic — Unit 2: Addition and Subtraction — Answer Key
Page 38–39: Introduction (Expenditure Table) - apteachers.in
Expenditure for 2 acres (double the 1-acre amount):
| Details of expenditure | 1 acre (₹) | 2 acres (₹) |
|---|---|---|
| Preparation of field | 2,545 | 5,090 |
| Seed bed and plantating | 4,507 | 9,014 |
| Removal of weeds | 1,235 | 2,470 |
| Fertilizers & pesticides | 4,700 | 9,400 |
| Harvesting | 4,125 | 8,250 |
| To heap and to thresh | 4,675 | 9,350 |
Page 40: Questions on Expenditure Table - 5th Maths Addition and Subtraction
1. Preparation of field + Seed bed = 2,545 + 4,507 = ₹7,052
2. Harvesting + Heaping & threshing = 4,125 + 4,675 = ₹8,800
3. Seed bed + Removal of weeds = 4,507 + 1,235 = ₹5,742
4. Total cost for 1 acre = 2,545+4,507+1,235+4,700+4,125+4,675 = ₹21,787
5. Total cost for 2 acres = 21,787 × 2 = ₹43,574
Page 40–42: Shankar & Sambaiah's Combined Expenditure
Shankar's expenditure (2 acres) = 43,574; Sambaiah's expenditure (1 acre) = 21,787
43,574 + 21,787 = 65,361 (worked out step by step using carrying in ones, tens, hundreds, thousands and ten-thousands place)
Example 1: 52,435 + 42,567 = 95,002
Do These (Page 44 – Addition)
1. 20,762 + 12,225 = 32,987
2. 13,482 + 26,742 + 37,323 = 77,547
Page 44–46: Subtraction — Mohan's Gain
Mohan earned ₹53,574; Investment ₹31,787
Gain = 53,574 − 31,787 = ₹21,787
Example 1: 49,543 − 26,874 = 22,669
Do These (Page 46 – Subtraction)
1. a) 43,521 − 38,445 = 5,076
1. b) 86,048 − 76,485 = 9,563
2. Number to be added to 13,672 to get 53,267 = 53,267 − 13,672 = 39,595
Page 48: Cloth Store — Questions
Silk sarees ₹9,899 | Cotton sarees ₹6,940 | Silk panche ₹2,785 | Door curtains ₹8,438 | Bed sheets ₹5,900 | Towels ₹2,350
1. Silk sarees − Door curtains = 9,899 − 8,438 = ₹1,461
2. Cotton sarees − Bed sheets = 6,940 − 5,900 = ₹1,040
3. Silk sarees + Silk panche = 9,899 + 2,785 = ₹12,684
4. Door curtains + Bed sheets + Towels = 8,438 + 5,900 + 2,350 = ₹16,688
5. Total spent = 9,899+6,940+2,785+8,438+5,900+2,350 = ₹36,312
Page 50: Project Work
This is a field activity — students collect actual population data (males, females, children, literates, illiterates) about their own village from the sachivalayam office and find the totals. Answers will vary based on each student's village data.
Example 1: Largest 5-digit number − Largest 4-digit number = 99,999 − 9,999 = 90,000
Example 2: Smallest 5-digit odd number + Largest 4-digit even number = 10,001 + 9,998 = 19,999
Page 52: Relation Between Addition and Subtraction
8 + 4 = 12 → Subtraction facts: 12 − 4 = 8 and 12 − 8 = 4
Example: 43,267 + 15,268 = 58,535 → Subtraction facts: 58,535 − 15,268 = 43,267 and 58,535 − 43,267 = 15,268
Example: 14 − 8 = 6 → Addition fact: 6 + 8 = 14; For 65,347 − 45,621 = 19,726 → Addition fact: 19,726 + 45,621 = 65,347
Simplify: 52,837 + 14,563 − 32,409 = 34,991
Exercise-1 (Page 54)
1. Total earnings = 37,645 + 25,367 = 63,012; Savings = 63,012 − 38,600 = ₹24,412
2. Total spent = 15,870 + 25,785 = 41,655; Money left = 52,490 − 41,655 = ₹10,835. He cannot buy another item costing ₹12,000 since only ₹10,835 remains, which is ₹1,165 short.
3. Milk to market = 25,545 − 15,625 = 9,920 litres
4. Total received = 2,500 + 1,300 = 3,800; Remaining = 3,800 − 3,100 = ₹700 → Option C) ₹700
5. Other number = 6,489 − 643 = 5,846 → Option A) 5846
6. Fill in the blanks:
| Addition | Subtraction Fact-1 | Subtraction Fact-2 |
|---|---|---|
| 7500 + 2500 = 10,000 | 10000 − 2500 = 7500 | 10000 − 7500 = 2500 |
7. a) 12,645 − 36,221 + 43,576 → Add 12,645+43,576 = 56,221; then 56,221 − 36,221 = 20,000
7. b) 40,376 − 20,568 + 37,364 → Add 40,376+37,364 = 77,740; then 77,740 − 20,568 = 57,172
Do These (Page 55 – Properties of Addition)
1. a) 27,543 + 56,409 = 56,409 + 27,543
1. b) 34,178 + 67,894 = 67,894 + 34,178
1. c) 88,998 + 0 = 88,998
1. d) 0 + 65,912 = 65,912 + 0
Do These (Page 56–57 – Rounding to Nearest Ten Thousand)
a) 28,456 → 30,000
b) 35,782 → 40,000
c) 43,248 → 40,000
Page 58–59: Estimating Sum and Difference
1. ₹158 + ₹143 ≈ ₹200 + ₹100 = ₹300
2. ₹7,890 − ₹3,295 ≈ ₹8,000 − ₹3,000 = ₹5,000
3. 6,776 − 2,373 ≈ 7,000 − 2,000 = 5,000
4. 257 − 163 ≈ 300 − 200 = 100 pages
Page 60–63: Profit and Loss
Cotton saree total cost = ₹900; Silk saree total cost = ₹5,500
1. Cotton saree sold for ₹1,100: Since SP (1,100) > CP (900), he makes a profit of ₹200.
2. Cotton saree sold for ₹400 each: Since SP (400) < CP (900), he makes a loss of ₹500. Reason for selling at a low price could be that the sarees were damaged, out of fashion, or he needed urgent cash, so he sold at clearance price.
Shopkeeper example: Cotton saree — CP ₹1,200, SP ₹1,400 → Profit = ₹200. Silk saree — CP ₹7,000, SP ₹8,500 → Profit = ₹1,500.
Damaged sarees: CP ₹1,200, SP ₹800 → Loss = ₹400
Example 1 (Amar the gold merchant): Cost = ₹50,000; Present rate = ₹57,000 → Profit = 57,000 − 50,000 = ₹7,000
Exercise-2 (Page 66)
1. Selling price = CP + Profit = 800 + 250 = ₹1,050
2. Selling price = 450 + 50 = ₹500
3. Geetha's spend = 75 × 2 = 150; Difference = 500 − 150 = ₹350
4. CP ₹800, SP ₹650 → SP < CP, so it is a loss of 800 − 650 = ₹150 → Option B) ₹150 loss
5. For a profit: Option B) selling price > cost price
6. Profit/Loss table:
| Item | Profit/Loss | How much |
|---|---|---|
| a) Rice bag (CP ₹750, SP ₹900) | Profit | ₹150 |
| b) Bed sheet (CP ₹635, SP ₹815) | Profit | ₹180 |
| c) Umbrella (CP ₹105, SP ₹90) | Loss | ₹15 |
Improve Your Learning (Page 68)
1. Selling price = 295 + 25 → Option b) Selling price = 295 + 25
2. Ram bought 5,000 ones = 5,000 toffees; Shyam bought 60 tens = 600 toffees; Difference = 5,000 − 600 = 4,400 → Option b) 4400
3. Blank = 4,591 + 36,782 = 41,373 (since 41,373 − 36,782 = 4,591)
4. Two classes collected 46,569 + 34,266 = 80,835; Amount to add to make ₹99,000 = 99,000 − 80,835 = ₹18,165
5. Total scoops sold = 1,178 + 983 = 2,161 scoops
6. Total cost = 1,200 (mangoes) + 100 (transport) = ₹1,300. Selling price = ₹1,400. Actual profit = 1,400 − 1,300 = ₹100, not ₹200 as claimed. His statement is incorrect because he forgot to include the ₹100 transport cost while calculating the cost price.
7. Any values where CP − SP = ₹500 work, e.g., Cost price = ₹3,000, Selling price = ₹2,500 (loss of ₹500).
8. Anita's total money = savings ₹2,150 + grandmother's gift ₹500 = ₹2,650; Amount still needed = 3,600 − 2,650 = ₹950
9. Income in 2019 = 6,25,320 + 64,200 = ₹6,89,520; Total earned in both years = 6,25,320 + 6,89,520 = ₹13,14,840
