National institutes of health office of extramural research Interview Questions, Process, and Tips

Answer:

24

Step-by-step explanation:

A + B = 40.

And at Rs 7 a kg for 40 kg, you want a total of Rs.280.

So the second equation is 9A + 4B = 280

From the first equation: B = 40 – A

and sub into the second equation:

9A + 4(40-A) = 280

9A + 160 – 4A = 280

5A = 120

A = 24.

And you should check: B should equal 40-24 = 16. Check with the final equation: 9*24 + 4*16 = 216 + 64 = 280. So it works.

Your answer, of course, is A = 24

740

72

There should be 5(2+2+1) decimal places in the answer and the decimal place should end with 2(3*2*2=12) so the correct answer is a, no need for calculator. You can rule out all the other options because it does not satisfy this condition.

One day’s work of A, B and C = (1/24 + 1/30 + 1/40) = 1/10.

C leaves 4 days before completion of the work, which means only A and B work during the last 4 days.

Work done by A and B together in the last 4 days = 4 (1/24 + 1/30) = 3/10.

Remaining Work = 7/10, which was done by A,B and C in the initial number of days.

Number of days required for this initial work = 7 days.

Thus, the total numbers of days required = 4 + 7 = 11 days.

( d ) 6 days

Before Swapping
_ _ _ _ _ _ _ Shilpa ……..Reena _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

After Swapping
_ _ _ _ _ _ _ Reena _ _ _ _ _ Shilpa _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
—————————–>14=17 <——————————-

So total number of girls in that row are 30

let no. of boys not participating be x
then the no. of girls not participating = x+5
no. of boys : girls participating = 3:2
given no.of boys participating = 15
therefore, the ratio is now 15:y(say)
then 3:2 = 15 : x
on solving 3/2 =15/y ie.., 3y =30 we get y =10
hence no. of girls participating =10
therefore total no of students paricipating = 15+10=25
total no of students in class =60 given
hence no. of students not participating = 60-25=35
therefore x+(x+5)=35
2x=30
x=15
therfore no of girls not participating =15+5=20
therefore total no of girls in class = no of girls
participating + no of girls not participating
=10+20
=30 is the answer

Fuel to go = x + (x/4)=5x/4
Fuel to come = x
now,
x+(5x/4) = 4.5
9x/4 = 4.5
9x = 18
x = 2 (Fuel to comeup)
Fuel to go will be:
2+(2/4) = 2 + (0.5) = 2.5

The work done by A in 8 days is = 8/ 12 = 2/3

Means A alone completes 2/3 part of work.

Remaining work which is (1–2/3) = 1/3 is completed by B in 8–2 = 6 days

So the complete work done by B in 6/(1/3) = 18 days.

B alone can complete the work in 18 days.

d

995