Mathematics
NULL
Medium
Question
Three boys average 15 years and their ages are in the ratio 3 : 5 : 7. What is the youngest boy’s age?
A
15
B
9
✓ Official correct answer
C
18
D
21
Community credibility
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A
15
No member explanations yet for this option.
B
9
No member explanations yet for this option.
C
18
No member explanations yet for this option.
D
21
No member explanations yet for this option.
Explanation
Ages 9, 15 and 21. Youngest = 9.