- A alone can complete a piece of work in 15 days and B & C together can complete the same work in 8 1/3 days. B is 100% more efficient than C. How many days is required to complete the work if A and C work together ?
12 days8 days6 days9 3/8 days5 daysOption D

LCM of 15 and 8 1/3 days = 75

efficiency of A = 75/15 = 5

efficiency of B and C = 75 * 3/25 = 9

let efficiency of C = 100

efficiency of B = 200

ratio of efficiency of B and C = 2 : 1

efficiency of B = 9 * 2/3 = 6

efficiency of C = 9 * 1/3 = 3

time = 75/(5 + 3) = 75/8 = 9 3/8 days - Rajat alone can complete a piece of work in ‘x’ days and Sujit alone can complete the same work in (x + 5) days. If they together can complete the same work in 6 days, then find in how days Sujit can complete the whole work ?
10 days6 days8 days5 days15 daysOption E

1/x + 1/x + 5 = 1/6

2x + 5 / x^2 + 5x = 1/6

x^2 + 5x = 12x + 30

x^2 – 7x – 30 = 0

x = 10 , – 3

Days can not come in negative, so that value of x = 10

Days taken by Sujit to complete the work = x + 5 = 15 days - A alone can complete a work in 25 days and B alone can complete same work in 45 days. How many days are taken by A and B together to complete 60% of work ?
14 days135/14 days68/7 days18/5 days9 2/5 daysOption B

LCM of 25 and 45 = 225

efficiently of A = 225/ 25 = 9

efficiently B = 225/45 = 5

days = 225/14 * 60/100 = 135/14 days - A and B can complete a work in 24 days and B and C together can complete the same work in 30 days. A and C together work for 15 days and after 15 days A and C left the work, remaining work done by alone B. If the efficiency ratio of A and B is 2 : 3, then find in how many days total work will be completed ?
28 days60 days40 days38 days25 daysOption C

LCM of 24 and 30 = 120

total work = 120

efficiency of A and B = 120/24 = 5

efficiency of B and C = 120/30 = 4

efficiency of A = 5 * 2/5 = 2

efficiency of B = 5 – 2 = 3

efficiency of C = 4 – 3 = 1

A and C together work for 15 days = (2 + 1) * 15 = 45

remaining work = 120 – 45 = 75

days required to complete remaining work = 75/3 = 25 days

total days = 15 + 25 = 40days - P , Q and R together can complete a work in 20 days and the ratio of time taken by P , Q and R is 8 : 6 : 3. How many days is taken by Q and R together to complete the whole work ?

18 days25 days26 days30 days32 daysOption B

Time ratio of P , Q and R = 8 : 6 : 3

LCM of 8, 6 and 3 = 24

efficiency ratio of P, Q and R = 24/8 : 24/6 : 24/3 = 3 : 4 : 8

let efficiency of P , Q and R = 3x , 4x and 8x respectively.

total work = 20 ( 3x + 4x + 8x ) = 300x

time taken by Q and R together complete the work = 300x / 12x = 25 days - The efficiency of Rohit is 40% more than Suraj. If Suraj alone can do a work in 14 days, then find how many days is taken by Rohit to complete the whole work ?
10 days15 days22 days13 days18 daysOption A

Efficiency of Suraj = 5x

Efficiency of Rohit = 5x * 140/100 = 7x

total work = 14 * 5x = 70x

time taken by Rohit to complete the work = 70x/7x = 10 days - A and B can do a work in 10 days B and C can do the same work in 12 days and A and C can do the same work in 15 days. How many days by A, B and C together to complete total work ?
5 days8 days14 days15 days6 daysOption B

LCM of 10 , 12 and 15 = 60

efficiency of A and B = 60/10 = 6

efficiency of B and C = 60/12 = 5

efficiency of A and C = 60/15 = 4

A + B + B + C + A + C = 15

A + B + C = 7.5

time = 60/7.5 = 8 days - 12 men do a work in 18 days. They started work together and after 8 days, 3 more joined with them. In how many days the remaining work will be completed ?
8 days9 days12 days18 days15 daysOption A

Let the remaining work completed in ‘x’ days

12 * 18 = (12 * 8) + (15 * x)

15x = 120

x = 8 days - Rita , Gita and Sita can do a piece of work in 24 days , 20 days and 15 days respectively. If they got total wages of rs. 3800, then find difference between the wages got by Sita and Gita.
500800480400620Option D

LCM of 24 , 20 and 15 = 120

total work = 120

efficiency of Rita = 120/24 = 5

efficiency of Gita = 120/20 = 6

efficiency of Rita = 120/15 = 8

difference = 3800 * 8 – 6/19 = rs.400 - If 12 men can complete a piece of work in 20 days and 15 women can complete the same work in 24 days, then in how many days 8 men and 8 women can complete the whole work ?
15 days18 days17 days12 days24 daysOption B

12 men * 20 days = 15 women * 24 days

m/w = 3/2

total work = 12 * 3 * 20 = 720

time = 720 / (8 * 3 + 8 * 2 ) = 720/40 = 18 days