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Weight Mental Maths
You have learnt to measure weight of an object in grams Convert the following:
and kilograms. Have you ever wondered how a goldsmith (a) 6,000 mg to g
or any jeweller weighs small pieces of jewellery! They (b) 7 mg to g
use weights that are smaller than grams. These are of (c) 4,750 g to kg
milligrams (mg). (d) 525 g to kg
1,000 g = 1 kg 1 g = 1,000 mg
1 1
1 g = kg 1 mg = g
1,000 1,000
Example 2: Fill in the blanks.
(a) 2 kg 350 g = ______ g (b) 6,210 g = ______ kg ______ g
(c) 2 g 325 mg ______ mg
Solution: (a) 1 kg = 1,000 g
So, 2 kg = 2 × 1,000 g = 2,000 g
2 kg 350 g = 2,000 g + 350 g = 2,350 g
(b) 6,210 g = 6,000 g + 210 g
= 6 kg + 210 g
= 6 kg 210 g
(c) 2 g = 2,000 mg
2 g 325 mg = 2,000 mg + 325 mg
= 2,325 mg
Capacity
Mental Maths
Capacity is measured in kilolitres (kL), litres (L) and Convert the following:
millilitres (mL).
(a) 4 L to kL
1 kL = 1,000 L 1 L = 1,000 mL (b) 2,000 L to kL
(c) 5,000 mL to L
1 L = 1 kL 1 mL = 1 L (d) 250 mL to L
1,000 1,000
Example 3: Fill in the blanks.
(a) 3 kL 475 L = ______ L (b) 6,245 L = ______ kL ______ L
(c) 3 L 625 mL = ______ mL (d) 1,045 mL = ______ L _____ mL
Solution: (a) 1 kL = 1,000 L
So, 3 kL = 3 × 1,000 L = 3,000 L
3 kL 475 L = 3,000 L + 475 L = 3,475 L
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