Akshay starts working on a job and continues for 15 days and completes

Question

Akshay starts working on a job and continues for 15 days and completes 36% of the work. To complete the work, he employs Monika and together they work for 20 days and completed the work. What will be the efficiency ratio of Akshay and Monika ?

(A) 7 : 5
(B) 4 : 3
(C) 5 : 3
(D) 1 : 3
(E) 3 : 1

(A) 7 : 5
(B) 4 : 3
(C) 5 : 3
(D) 1 : 3
(E) 3 : 1

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ManifestDreamMBA · Answer

W=RT

Let Rate of work for Akshay be A and for Monika be M
0.36 = A*15
A = 36/1500 = 12/500

0.64 = (A+M)*20
A+M = 64/2000 = 16/500

M = 16/500 - 12/500 = 4/500

A: M = 12:4 = 3:1

GMATinsight · Answer

Let work = 100 units

Akshay's work of 15 days = 36 unit

Akshay and Monika's 20 day work = 100-36 = 64 units

Since akshay does 36 units in 15 days so in 20 days Akshay will do = 36*(20/15) = 48 units

i.e. Monika's work of 20 days = 64-48 = 16

efficiency ratio of Akshay and Monika (for 20 days) = 48:16 = 3:1

Answer: Option E

Related Video:  
  https://www.youtube.com/watch?v=PkC08H0IPGw

Abhiswarup · Answer

Let total work be 100 units

A does 36 units in 15 days. A does 36/15 units of work in 1 day

Now A employs B also and does 64 Units of work together in 20 days
Lets B does Y units of work in 1 day

36/15*20+20Y=64
Solving Y=4/5

A/B= 12/5:4/5=3:1

Missinga · Answer

A*15=36%
A=0.36/15= 12/500

Also, (A+M)*20= (100-36)%
A+M=0.64/20=16/500
M=(16/500)-(12/500)= 4/500

A:M= (12/500):(4/500) = 12:4= 3:1

Answer: E

Dereno · Answer

Akshay continues to work for 15 days and completes 36% of the work.

Let the total work be 100 units.

Akshay working for 15 days finishes 36 units.

Remaining work = 100-36 = 64 units.

Monika and Akshay work for 20 days to complete 64 units .

20 A + 20 M = 64

36 unit = 15 days 
? = 20 days.

In 20 days , Akshay completes 48 units.

Remaining 16 units (64-48= 16 units) is completed by Monika in 20 days.

Akshay : Monika = 48:16 =  3:1

Another Approach:

Efficiency = work / time

Given: Akshay does 36% work in 15 days.

Ea = 36/15 = 12/5

If Akshay does 36% in 15 days, using UNITARY METHOD, in 20 days he completes 48 % of work.

If 36% is completed, the. Remaining work is 64% . ( total work =100%)

Out of 64% , Akshay completed 48% in 20 days. Job remaining is 16%. Which is completed by Monika in 20 days.

Em = 16/20 = 4/5

Ea: Em = 12/5 :4/5 = 12:4 = 3:1.

rohitz98 · Answer

Given Akshay completes 36% of work in 15 days; Hence the rate of Akshay is (36/100)/15 = 1/(125/3)
Remaining work is 64/100 which is completed jointly by monika and akshay in 20 days

If x is no. of days taken by monika to complete the entire work then,

1/(125/3) + 1/x = (64/100)/20

Which gives x = 125

Hence ratio of days taken by akshay : monika = (125/3):125
Hence ratio of speed of akshay : monika = 3:1  Option E

Sketchitesh · Answer

36% work done in 15 days => 100% work by Akshay in days (A) => 100*15/36

64% work done in 20 days => 100% work done by both in days (A + M) = 100*20/64

\frac{1}{(A+M)} = \frac{1}{A} + \frac{1}{M }

\frac{64}{(2000)} = \frac{36 }{1500} + \frac{1}{ M }

=>  \frac{(64 * 1500)}{ (2000*36)} = \frac{A}{M }

=> A/M = 1:3

Note that ratio of days in inverse of Ratio of efficiency so Ratio of Efficiency E (A/ M) = 3:1

Answer is Option E

Akshay starts working on a job and continues for 15 days and completes

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