4
Q:

# K can finish the work in 18 days and L can do the same work in 15 days. L worked for 10 days and left the job. In how many days, K alone can finish the remaining work ?

 A) 5.5 days B) 6 days C) 4.2 days D) 5 days

Explanation:

L's 10 days work = $\inline \fn_jvn \small \left ( \frac{1}{15}\times 10 \right )= \frac{2}{3}$
Remaining work = $\inline \fn_jvn \small \left ( 1-\frac{2}{3} \right )=\frac{1}{3}$
Now, $\inline \fn_jvn \small \frac{1}{18}$ work is done by K in one day
$\inline \fn_jvn \small \frac{1}{3}$ work is done by K in $\inline \fn_jvn \small \left ( 18\times \frac{1}{3} \right ) = 6 days$

Q:

P and Q were assigned to do a work for an amount of 1200. P alone can do it in 15 days while Q can do it in 12 days. With the help of R they finish the work in 6 days. Find the share of R ?

 A) 120 B) 240 C) 360 D) 180

Explanation:

1/15 + 1/12 + 1/R = 1/6, we got R = 60 (it means R will take 60 days to complete the work alone)
so ratio of work done by P:Q:R = 1/15 : 1/12 : 1/60 = 5 : 4 : 1
so R share = (1/10)x1200 = 120.

3 81
Q:

A group of men can complete a job in K hours. After every 4 hours, half the number of men working at that point of time leave the job. Continuing this way if the job is finished in 16 hours, what is the value of K ?

 A) 7 hrs B) 7.5 hrs C) 8 hrs D) 8.25 hrs

Explanation:

Let there are L men

job requires LK man hours.

job completed in first 4 hrs = Lx4 = 4L
job completed in next 4 hrs = 4xL/2 = 2L
job completed in next 4 hrs = 4xL/4 = L
job completed in last 4 hrs = 4xL/8 = L/2
4L + 2L + L + L/2 = KL
K = 7+1/2 = 7.5 hours.

2 25
Q:

A can do a work in 9 days, B can do a work in 7 days, C can do a work in 5 days. A works on the first day, B works on the second day and C on the third day respectively that is they work on alternate days. When will they finish the work ?

 A) [7 + (215/345)] days B) [6 + (11/215)] days C) [6 + (261/315)] days D) [5 + (112/351)] days

Explanation:

After day 1, A finishes 1/9 of the work.

After day 2, B finishes 1/7 more of the total work. (1/9) + (1/7) is finished.

After day 3, C finishes 1/5 more of total work. Total finished is 143/315.

So, after day 6, total work finished is 286/315.

Now remaining work = 315 - 286 = 29 /315

On day 7, A will work again

Work will be completed on day 7 when A is working. He must finish 29/315 of total remaining work.

Since he takes 9 days to finish the total task, he will need 261/315 of the day.

Total days required is 6 + (261/315) days.

3 40
Q:

One girl can eat 112 chocolates in half a minute, and her boy friend can eat half as many in twice the length of time. How many chocolates can both boy and girl eat in 12 seconds ?

 A) 44 B) 32 C) 56 D) 49

Explanation:

Girl eats 112 chocolates in 30 sec
so she can eat in 12 sec is 12 x 112/30 = 44.8 chocolates.

Her boy friend can eat one-half of 112 in twice of 30 sec
so he can eat 56 in 60 sec
Then he can eat in 12 sec is 56 x 12/60 = 11.2 chocolates.

Hence, together they can eat
=> 44.8 + 11.2
56 chocolates in 12 seconds.

5 31
Q:

Two boys and a girl can do a work in 5 days, while a boy and 2 girls can do it in 6 days. If the boy is paid at the rate of 28\$ a week, what should be the wages of the girl a week ?

 A) 24 \$ B) 22 \$ C) 16 \$ D) 14 \$

so a girl will be paid 28x $\inline \fn_jvn \frac{\frac{2}{45}}{\frac{7}{90}}$ = 16 \$.