If a:2 = b:5 then how many % of b is a
(a) 20
(b) 30
(c) 40
(d) 50
WBBSE
Class X
Mathematics
Ratio And Proportion
01 Mark
2025
(c) 40
Explanation:
⇒ a / 2 = b / 5
⇒ a × 5 = b × 2
⇒ a = (2/5) b
Now, percentage of b that a represents:
(a / b) × 100 = (2/5) × 100 = 40%
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