Can do a piece of work in 24 days B can do it in 30 days in how many days can they complete it if they work together?

A and B can do a piece of work in = 40 daysB and C can do a piece of work in = 30 daysC and A can do a piece of work in = 24 days

(A+B)’s 1-day work =`1/40`

(B+C)’s 1-day work =`1/30`

(C+A)’s 1-day work =`1/24`

(i) [(A+B)+(B+C)+(C+A)]’s 1 day work = `1/4+1/30+1/24`

`=(3+4+5)/120`

`=12/120=1/10`

i.e. (A+B+B+C+C+A)'s 1-day work =`1/10`

i.e. 2 (A+B+C)'s 1-day work =`1/10`

∴ (A+B+C)'s 1-day work =`1/10xx1/2`

`=1/20`

∴ (A+B+C) can do the work in = 20 days

(ii) A's 1-day work =`1/20-1/30`

`=(3-2)/60=1/60`

∴ A can do the work in 60 days

B's 1-day work =`1/20-1/24`

`=(6-5)/120=1/120`

∴ B can do the work in 120 days

 now, C's 1-day work =`1/20-1/40`

`=(2-1)/40=1/40`

C can do the work in 40 days

Hence A can do the work in = 60 days

B can do the work in = 120 days

C can do the work in = 40 days

Question 7 Time and Work Exercise 11.1

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Answer:

Every task necessitates a specific amount of time and a specific workforce, or the number of individuals who will complete the task.

Work is usually categorised as a "1" unit. This time and and work concept is a follow-up to direct and inverse proportion.

The given details are,

A and B can do a piece of work in = 18 days

Work done by A and B in 1 day = 1/18

B and C can do a piece of work in = 24 days

Work done by B and C in 1 day = 1/24

A and C can do a piece of work in = 36 days

Work done by A and C in 1 day = 1/36

By adding A, B and C we get,

2(A+B+C) one day work = 1/18 + 1/24 + 1/36

= (4+3+2)/72 (by taking LCM for 18, 24 and 36 which is 72)

= 9/72

= 1/8

A+B+C one day work = 1/(8×2) = 1/16

∴ A, B and C together can finish the work in = 1/(1/16) = 16days.

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The Staff Selection Commission (SSC) has released the SSC MTS Result for the Paper I Examination which was held from 5th July to 26th July 2022. The candidates who are qualified in the SSC MTS Paper I are eligible for the Paper II, the paper II will be held on 6th November 2022. A total of 7709 vacancies are released, out of which 3854 vacancies are for MTS Group age 18-25 years, 252 vacancies are for MTS Group age 18-27 years and 3603 vacancies are for Havaldar in CBIC.