SSC CGL 20191)A and B can do a piece of work in 6 days and 8 days, respectively. With the help of C, they completed the work in 3 days and earned Rs. 1848. What was the share of C ?
Rs. 231
Let the total work be 24 units.
(\because LCM of 6, 8 and 3 is 24.);
Efficiency of A = 24/6 = 4;
Efficiency of B = 24/8 = 3;
Efficiency of A, B and C = 24/3 = 8;
Efficiency of C = 8 - 4 - 3 = 1;
Ratio of the efficiency of A, B and C = 4 : 3 : 1;
Total earning = 1848;
Share of C = \(\frac{1}{4 + 3 + 1} \times 1848 = \frac{1}{8} \times 1848\) = Rs.231
SSC CGL 20192)Pipes A, B and C can fill a tank in 30 h, 40 h and 60 h respectively. Pipes A, B and C are opened at 7 a.m., 8 a.m., and 10 a.m. respectively on the same day. When will the tank be full?
9.20 p.m.
Let the total work be 120 units.|
(\because LCM of 30, 40 and 60 be 120.);
Efficiency of pipe A = 120/30 = 4 units/hr;
Efficiency of pipe B = 120/40 = 3 units/hr;
Efficiency of pipe C = 120/60 = 2 units/hr;
Work done by pipe A in 3 hr(7 am to 10 am) =\( 4 \times 3 \)= 12;
Work done by pipe B in 2 hr(8 am to 10 am) = \(3 \times 2\) = 6;
remaining work = 120 - 12 - 6 = 102 units;
At 10 am, all pipes are opened.
So, time taken by all pipes to complete the remaining work =\( \frac{112}{4 + 3 + 2} = \frac{102}{9} = 11\frac {3}{9} \)= 11hr 20 min;
Time when tank will be filled = 10 am + 11 hr 20 min = 9 .20 p.m.
SSC CGL 20193)A certain numberof persons can complete a work in 34 days working 9 hours a day. If the number of persons is decreased by 40%, then how many hours a day should the remaining persons work to complete the work in 51 days?
10
Let the number of persons be x.
Total work = \(34 \times 9x\) = 306x;
Now, number of person = 0.6x;
\(0.6x\times h \times 51\) = 306x;
h = 306/30.6 = 10;
therefore 10 hours a day should the remaining persons work to complete the work in 51 days.
SSC CGL 20194)To do a certain work, the ratio of efficiency of A to that of B is 3 : 7. Working together, they can complete the work in \(10\frac{1} {2} \)days. They work together for 8 days. 60% of the remaining work will be completed by A alone in:
5 days
Efficiency ratio of A to B = 3 : 7;
Let the efficiency of A and B be 3x and 7x respectively.
Total efficiency = 3x + 7x = 10x;
Time taken by A and B to complete the work =\( 10\frac{1}{2} \)= 21/2;
Total work = days to complete the work \times efficiency = \(10x \times 21/2\) = 105x;
Work done in 8 days = \(10x \times 8 \)= 80x;
Remaining work = 105x - 80x = 25x;
60% of the remaining work = \(25x \times \frac{60}{100}\) = 15x;
Time taken by A to complete 15x work = 15x/3x = 5 days
SSC CGL 20195)A is as efficient as B and C together. Working together A and B can complete a work in 36 days and C alone can complete it in 60 days. A and C work together for 10 days, then B alone will complete the remaining work in :
110 days
1/A = 1/B + 1/C
1/A + 1/B = 1/36
C = 60
solving for A and B we get A = 45 , B = 180
Let B finishes remaining work in x days, then
10/A + 10/C + x/B = 1
⇒ 10/45 + 10/60 + x/180 = 1
⇒ x = 110
SSC CGL 20196)A can do one-third of a work in 15 days, B can do 75% of the same work in 18 days and C can do the same work in 36 days. B and C work together for 8 days. In how many days will A alone complete the remaining work?
20 days
SSC CGL 20197)25 persons can complete a work in 60 days. They started the work. 10 persons left the work after x days. If the whole work was completed in 80 days, then what is the value of x ?
30
SSC CGL 20198)4 men and 5 women can complete a work in 15 days, whereas 9 men and 6 women can do it in 10 days. To complete the same work in 7 days, how many women should assist 4 men?
13
SSC CGL 20199)To do a certain work, the ratio of the efficiencies of X and Y is 5 : 4. Working together, they can complete the same work in 10 days. Y alone starts the work and leaves after 5 days. The remaining work will be completed by X alone in:
14 days
SSC CGL 201910)A can do 40% of a work in 12 days, whereas B can do 60% of the same work in 15 days. Both work together for 10 days. C completes the remaining work alone in 4 days. A, B and C together will complete 28% of the same work in :
2 days
A can do 40% of a work in 12 days, whereas B can do 60% of the same work in 15 days. Both work together for 10 days. C completes the remaining work alone in 4 days. A, B and C together will complete 28% of the same work in :
Let work be 1, A can do work in A days, B can do work in B days and C can do work in C days then
\({12\over A} = 0.4\), \({15 \over B} = 0.6\), A= 30 days, B = 25 days ; let C complete remaining work in 4 days after A and B works for 10 days
\( {10 \over 30}+{10\over 25}+ {4\over C} = 1\); C = 15 days.
Let the 28% work be completed in x days
\( {x \over 30}+{x\over 25}+ {x\over 15} = 0.28\)
Solve for x ; it will be 2 days