Question

A Boy Run For 10 Min At A Uniform Speed Of 9Km/H.At What Speed Should He Run For The Next 20 Min So That The Average Speed Comes To 12Km/H.

Answer 1

Answer:

25.5

Explanation:

$30 \div 60 \times 12 - 10 \div 60 \times 9 \div 20 \div 30$