How Cheenta works to ensure student success?

Explore the Back-StoryThis is a problem from TOMATO Problem number 2, useful for ISI and CMI entrance exam based on Men and Job.

**Problem:**

If m men can do a job in d days, then the number of days in which m+r men can do the job is

(A) d+r; (B) $\frac{d}{m} (m+r)$ ; (C) $\frac {d}{m+r}$ ; (D) $\frac {md}{m+r}$;

**Discussion:**

If m men can do a job in d days,

Then m men does $\frac {1}{d}$ job in 1 day

Then 1 man does $\frac {1}{md}$ job in 1 day

Then m+r men does $\frac {m+r}{md}$ job in 1 day

Then m+r men does 1 job $\frac {md}{m+r}$ days.

Hence answer is $\frac {md}{m+r}$ days (D)

**What is this topic:**Arithmetic**What are some of the associated concepts:**Unitary Method**Where can learn these topics:**Cheenta I.S.I. & C.M.I. course, discusses these topics in the ‘Arithmetic’ module.**Book Suggestions:**Arithmetic by K.C. Nag

Cheenta is a knowledge partner of Aditya Birla Education Academy

Advanced Mathematical Science. Taught by olympians, researchers and true masters of the subject.

JOIN TRIALAcademic Programs

Free Resources

Why Cheenta?

Online Live Classroom Programs

Online Self Paced Programs [*New]

Past Papers

More