Page 123 - Start Up Mathematics_5

Length

Example 13: Add 93 km 15 dam and 32 km 23 dam and write the answer in kilometres.

Solution: 93 km 15 dam = 93.15 km Alternate Method
32 km 23 dam = + 32.23 km km dam
125.38 km 93 15
+ 32 23
125 38

125 km 38 dm = 125.38 km

Example 14: Subtract 32 km 82 cm from 84 km 67 cm.

Solution: Alternate Method
9 9 9 km cm
3 10 10 10 16
84 km 67 cm = 8 4 . 0 0 0 6 7 km 3 10 10 10 16
9 9 9
32 km 82 cm = – 3 2 . 0 0 0 8 2 km 8 4 0 0 0 6 7
5 1 . 9 9 9 8 5 km – 3 2 0 0 0 8 2

5 1 9 9 9 8 5

So, 84 km 67 cm – 32 km 82 cm = 51 km 99985 cm.

Weight

Example 15: Add 9 kg 73 g, 12 kg 125 g and 6 kg 54 g and write the answer in kilograms.

Solution: 1 1 Alternate Method
9 kg 73 g = 1 9 . 0 7 3 kg kg g

12 kg 125 g = 1 2 . 1 2 5 kg 1 1
6 kg 54 g = + 6 . 0 5 4 kg 1 9 0 7 3
2 7 . 2 5 2 kg 1 2 1 2 5
+ 6 0 5 4
2 7 2 5 2

27 kg 252 g = 27.252 kg

Example 16: Subtract 23 hg 76 dg from 79 hg 85 dg and write the answer in hectograms.

Solution: 7 15 Alternate Method
79 hg 85 dg = 7 9 . 0 8 5 hg hg dg
23 hg 76 dg = – 2 3 . 0 7 6 hg 7 9 0 8 5
7 15
5 6 . 0 0 9 hg
– 2 3 0 7 6
5 6 0 0 9

56 hg 9 dg = 56.009 hg

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