∵ Each tablet weighs = 40 mg
∴ The weight of 2,00,000 tablets = 2,00,000 × 40 = 80,00,000 mg
∴ The total weight of all the tablets in the box = 80,00,000 mg
We know 1 g = 1,000 mg
∴ Weight of the box having all tablets = 80,00,000 ÷ 1,000 = 8,000 g
And, as 1 kg = 1,000 g
∴ Weight of the box having all tablets = 8,000 ÷ 1,000 = 8 kg
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