Uttarakhand open university Interview Questions, Process, and Tips

AB

Correct option is C)
Let be students are consider as child
Let the age of child added later be x years.
average age of 12 children =20 years
∴ Total age of 12 children =20×12=240 years
After one more child is added-
Average of 13 children =20−1=19 years
Average age of 13 children =
13
sum of 12 children+x
​

19=
13
240+x
​

⇒240+x=247
⇒x=247−240=7 years
Hence the age of child added later is 7 years.

( d ) 6 days

12

we know,
area=b*h
b gets increased by 20% i.e (b+0.20b)
h gets decreased by 20% i.e (h-0.20h)
rewriting the equation(area=b*h),
area=(b+0.20b)*(h-0.20h)
area=b(1+0.20)*h(1-0.20)
area=b(1.20)*h(0.80)
area=b*h*(1.20)*(0.80)
area=b*h*(0.96)
i.e new area=0.96 times the original area
if 100% was the original area,it has decreased to 96%
so,100%-96%= 4%

451 times.
Explanation: There are 60 minutes in an hour.
In ¾ of an hour there are (60 * ¾) minutes = 45 minutes.
In ¾ of an hour there are (60 * 45) seconds = 2700 seconds.
Light flashed for every 6 seconds.
In 2700 seconds 2700/6 = 450 times.
The count start after the first flash, the light will
flashes 451 times in ¾ of an hour.

Answer is 124 because in this series is cube root sequence 2 cube root is 8 ,3 cube root is 24,4 cube root is 64, 5 cube root is 125 but there is 124 which is wrong ,6 cube root is 216 ,7 cube root is 343 .

C

0.255555…..

= 100 + 100 = 200 m

Time taken by train = 10 sec.

∵ Speed = Distance/Time

⇒ Speed of train = 200/10 = 20 m/sec.

∴ Speed of train = 20 × 18/5 = 72 kmph.

In question they left 10 seconds