A certain job was assigned to a group of men to do in 20 days. But 12 men did not turn up for the job and the remaining men did the job in 32 days. The original number of men in the group was:

see full answer

Your Exam Success, Personally Taken Care Of

1:1 expert mentors customize learning to your strength and weaknesses – so you score higher in school , IIT JEE and NEET entrance exams.

An Intiative by Sri Chaitanya

answer is C.

(Unlock A.I Detailed Solution for FREE)

Best Courses for You

JEE

NEET

Foundation JEE

Foundation NEET

CBSE

Detailed Solution

Let the original no. of men in the group be 𝑥.
No' of days required by 𝑥 men to do the job = 20
So, no. of days required by 1 𝑚𝑎𝑛 to do the job = 20 × 𝑥 = 20𝑥
No of men who did not turn up for the job = 12
Remaining no. of men = (𝑥 − 12)
So, no. of days required by (𝑥 − 12) men to do the job = 20𝑥
(𝑥−12)
Given, (𝑥 − 12) men did the job in 32 days. By the problem,

20𝑥
𝑥 − 12 = 32
⇒ 20𝑥 = 32(𝑥 − 12)
⇒ 20𝑥 = 32 𝑥 − 384

384
⇒ 32𝑥 − 20 𝑥 = 384 ⇒ 12𝑥 = 384 ⇒ 𝑥 =
12

= 32

Watch 3-min video & get full concept clarity