Page 104 - Start Up Mathematics_5

EXERCISE 7.1

1. Colour the pictures to show the addition.

(a) + =

(b) + =

2. Add.

(a) 60.28 and 71.43 (b) 59.8 and 37.04 (c) 18.2; 25.36 and 90.08

(d) 345.21 and 126.72 (e) 2,104.68; 521.29 and 173.8 (f) 13.246 and 76.08
(g) 92.21; 706.45 and 8.012 (h) 316.18; 24.2 and 50.36 (i) 78.61 and 89.025

3. Subtract.
(a) 39.26 from 50.04 (b) 105.026 from 317.54 (c) 204.194 from 400.62

(d) 1,123.7 from 5,604.21 (e) 53.89 from 2,235.67 (f) 12.029 from 134.72

(g) 8.075 from 120.23 (h) 5.64 from 1,000.26 (i) 371.06 from 400.71
4. Simplify.

(a) 71.26 + 40.79 – 31.8 (b) 15.24 – 6.35 + 12.9 (c) 65.79 + 29.103 + 38.921
(d) 99.99 – 9.88 – 19.65 + 30.2 (e) 999.99 + 1.11 – 258.67 (f) 134.88 – 98.075 – 6.27

(g) 68.145 + 11.063 – 0.024 (h) 8.20 – 1.65 + 6.79 – 2.84 (i) 21.49 + 17.21 – 20.149

Word Problems on Addition and Subtraction

Example 5: Ranu spent ` 748.50 on jeans, ` 108.25 on a scarf and ` 526.45 on a shirt.
How much money did Ranu spend in all?
Working
Solution: Money spent on jeans = ` 748.50
2 1 1
Money spent on scarf = ` 108.25 7 4 8 . 5 0
Money spent on shirt = ` 526.45 1 0 8 . 2 5

Total money spent = ` 748.50 + ` 108.25 + ` 526.45 + 5 2 6 . 4 5
= ` 1,383.20 1 3 8 3 . 2 0
Thus, Ranu spent ` 1,383.20 in all.

Example 6: Mary bought 3.5 m of red ribbon and 1.25 m of green ribbon. How much pink

ribbon should she buy in order to have a total length of 5.25 m of ribbons?

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