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Q:
A) 28 km/h | B) 30 km/h |
C) 40 km/h | D) 20 km/h |
Answer: D) 20 km/h
Explanation:
Explanation:
Let the normal speed be x km/h, then
x (x + 20) - 16 (x + 20) = 0
(x + 20 ) (x - 16) =0
x = 16 km/h
Therefore (x + 4) = 20 km/h
Therefore increased speed = 20 km/h