A boy goes to the market at a speed of 10 kmh"1 and returns at a speed of 5 kmh1 . If he takes 3 hours in all, what is the distance between his home and the market ?
Let the distance = x
Time taken = (x/10 + x/5) hr
x/10 + x/5 = 3. 3x/10 = 3 ∴ x = 10 km
If a 100m-long train crosses a bridge of length 10m in 22 seconds, then the time taken by the train to cross a pole is
Speed of train = 100+10/22 = 5 ms-1
∴ Time taken to cross a pole = 100/5 = 20sec
A man can row 8 kmh"1 in still water. If the river is running at 2 kmh1 , it takes 4 hrs more upstream than to go downstream for the same distance. Then the distance is given by
Let the distance be x.
∴ x/8-2 - x/8+2 = 4 x/6 - x/10 = 4
5x-3x/30 = 4 ∴ 2x = 120; x = 60 km.
A, B and C contract a work for Rs 1500. TogetherAand Bare supposed to do of the work. How much does C get ?
(A + B) did 2/5 of work.
∴ C did 1- 2/5 = 3/5 of work.
∴ (A + B)'s share : C's share = 2/5 : 3/5 = 2 : 3
∴ C's share = 1500/5 x 3 = 900
If 'A' is thrice as fast as B, and is therefore able to finish a work in 40 days less than B, find the time in which they can do it working together.
If A does a wrok in 1 day then B does it in 3 days (three fast), ie if diff is 2 days then A does then work in 1 day and B in 3 days. But the difference is 40 days. So A does the work in 20 days and B in 60 days.
Now A and B together will do the work in
20x60/20+60 = 1200/80 = 15 days.
Direction (Q. 6 - 10) : The table given below gives the number of days worked by employees of 5 grades A, B, C, D and E in different departments.
The number of days worked in Finance department was the highest for Grade
Employees of which grade worked the least considering all the departments ?
Grade E in Finance
Approximate average number of days worked by employees in Grade D is equal to
Approx avg = 1273/4 = 318
If employees work 8 hours a day, then total time consumed by Grade C employees is equal to
Total days of C = 310 + 322 + 315 + 310 = 1247 days
∴ No. of hrs = 1257 x 8 = 10056 hrs.
Average number of days worked by employees of all grades in Finance department is equal to
Required avg = 1470/5 = 294
@ Jenisys Systems Pvt Ltd