Some persons can do a piece of work in 84 days. Two times the number of such persons will do half of the same work in how many days?
Answer & explanation
Correct answer: option 1
Formula to be used here,
⇒ \(\frac{M_1\;×\;D_1}{M_2\;×\;D_2}\) = \(\frac{W_1}{W_2}\),
where, M = No. of Men, D = No. of Days, W = Work,
⇒ Putting in the values,
⇒ \(\frac{A\;×\;84}{2A\;×\;D_2}\) = \(\frac{1}{1/2}\)
⇒ D2= 21 days,