Question 15 - I have already answered in your other post.
Question 16
Area = 250 ft²
increase by 10% = 10% x 250 = 0.1 x 250 = 25
Area after 10% increased = 250 + 25 = 275 ft²
increase by 20% = 20% x 275 = 0.2 x 275 = 55
Area after 20% increased = 275 + 55 = 330 ft²
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Answer : Area after remodelled = 330 ft² (Answer D)
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