C-03-Q169mediumsingle_mcq

Rafiq alone 10 days, Shafiq alone 15 days. Together they finish in—

a $6$ days
b $5$ days
c $25$ days
d $12.5$ days

ব্যাখ্যা

Combined one-day work is $\dfrac{1}{10} + \dfrac{1}{15} = \dfrac{1}{6}$ , so together they take days. The reciprocal of the summed rates gives the joint time.

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Algebraic Expressions — সব প্রশ্ন দেখুন (219টি) →