- In a mixture of milk and water the proportion of water by weight was 60%. If in 50 l of mixture 10 l water was added, what would be the percentage of water?
45 1/2%72%66 2/3%35%NoneOption C

Solution:

Milk : Water 40:60

2:3.

5—-50

2—-?–> 20 l

3—-?—> 30l

10l water added

Then new ratio 20/ (30+10) = 20/40=1:2.

%ge of water=40/60 *100

=400/6=66 2/3%. - In an examination on which full marks were 1000. A got 20% less than B. B got 25% more than C. C got 20% less than D. If A got 400 marks, what percentage of full marks was obtained by D?
56%62%60%50%NoneOption D

Solution:

A’s Mark=400

B’s Mark=400*100/80

=500.

C’s Mark=500*100/125

=400.

D’s Mark=400*100/80

=500.

%ge =500/1000 *100

=50%. - In a group of 8 boys and 4 girls, four children are to be selected. In how many different ways can they be selected such that at least one boy should be there?
520494375455NoneOption B

Solution:

Atleast one boy=12c4 – 4c4

= (12*11*10*9)/(4*3*2*1) – 1

=495-1

=494. - In a test consisting of 100 questions carrying one mark each, Swetha answers 60% of the first 50 questions correctly. What percent of the other 50 questions does she need to answer correctly to score 75% on the entire test?
90%85%80%82%NoneOption A

Solution:

60%————–x%

———75%——–

x-75————-15

(x-75)/ 15 = 50/50

x-75=15

x=90%. - A bag contains 20 ball marked 1 to 20. One ball is drawn at random. Find the probability that it is marked with a number multiple of 5 or 7.
4/31/23/105/6NoneOption C

Solution:

Multiple of 5 and 7 is 1, 5, 7, 10, 14, 15, 20.

Probability= 4/20 +2/20

=1/5+1/10

=3/10. - A right cylindrical vessel is full with water. How many right cones having the same diameter and height as that of the right cylinder will be needed to store that water?
3564NoneOption A

Solution:

Volume of the cylindrical vessel =πr^{2}h

Volume of cone=1/3 πr^{2}h

No of cones= (πr^{2}h) / (1/3 πr^{2}h)

=3. - 24 men can complete a piece of work in 10 days and 16 women can complete the same piece of work in 20 days. What is the respective ratio between the amount of work done by 30 men in 1 day and the amount of work done by 20 women in 1 day?
6:53:12:14:3NoneOption C

Solution:

(24M*15)/1 =(16W*20)/1

3M=4W

M=4/3W

30M :20W

30*4/3W=20W

Ratio 40:20=2:1. - Two vessels A and B contain milk and water mixed in the ratio 5 : 4 and 2 : 3. When these mixture are mixed to form a new mixture containing half milk and half water, they must be taken in the ratio
8:59:57:34:1NoneOption B

Solution:

Take milk

5/9———-2/5

——-1/2——

(1/2-2/5)—-(5/9-1/2)

1/10: 1//18

Required ratio 9:5. - Out of 8000 seats in a stadium 500 were not sold. Of the tickets sold, 30% were sold at half price and the remaining tickets were sold at the full price of Rs20. The total revenue from the ticket sales was
Rs127500Rs120000Rs115000Rs132500NoneOption A

Solution:

Total revenue=7500*30/100*10+ 7500*70/100*20

=22500+105000

=Rs127500. - A travelled 1200 km by Air which formed 2/5 of his trip. 1/3 of the whole trip, he travelled by the car and the rest of the journey he travelled by train. The distance travelled by the train was
950km900km650km800kmNoneOption D

Solution:

Total distance travelled by A be x

x*2/5=1200

=3000km.

Distance travelled by Car=1/3*3000=1000.

Distance travelled by train=3000 – (1200+1000)

=800km.