**Question-1****Explanation**

**Ranganath Kurup went to an egg shop. He was happy to see that the price of eggs had come down. Yes. This price of eggs had been reduced by 20%. This helped him to buy ten eggs more for Rs. 160. What was the price of fifty eggsin case the shopkeeper had not brought down the price of eggs.?**

**Options :**

a)Rs.160

b)Rs.183

c)Rs.247

d)Rs.192

**Answer: d) Rs. 192**

Ranganath Kurup could buy ten eggs more for Rs. 160.

Cost of 10 eggs=20 eggs=20%of160=20/100*160=32

Cost of 1 egg=Rs. 3.20

Price of one egg before reduction=120/100*3.20=Rs.3.84

Then cost of 50 eggs=Rs. 3.84*50=Rs.192.

**Question-2****Explanation**

**The age of Kashyap and his father Sathish are in the ratio 2:5 Elght years hence, the ratio of their ages will be 1:2. What is 450% of the present age of Kashyap?**

**Options :**

a)64

b)72

c)82

d)92

**Answer: b) 72 **

Let the present age of Kashyap and Sathish be x and y respectively

Therefore x/y=2/5

Hence 5x=2y

5x-2y=0….(1)

It is given in the problem that after 8 years it will be in the ratio 1:2

Therefore(x+8)/(y+8)=1/2

Or 2x+16=y+8

2x-y=-8

4x-2y=-16……..(2)

Resolving(1)and (2)

5x-2y-4x+2y=0+16

Therefore x=16 and y=40

So present age of Kashyap=x=16

Present age of Sathish(father)=y=40

450% of the age of Kashyap=(450/100)*16=72years

**Question-3****Explanation**

**There are two groups and 300% of 40% of the strength of number one group is twelve more than 3/5 th of the strength of the second group. The ratio of the numbers of these two groups is 5:8 find out the product of strength of these two groups?**

**Options :**

a)3200

b)4800

c)5400

d)4000

**Answer: d) 4000 **

Let the strength of group one be x

And that of group two be y

Then it is given xX40/100X300/100=3/5Xy+12

120x/100=3/5XXy+12

6x/5=3y/5+12

6x/5-3y/5=12

6x-3y=60………………..(1)

The strength of the two groups is in the ratio 5:8

x/y =5/8

8x-5y=0….(2)

Solving (1)and (2)

Multiplying(1)by 5 30x-15y=300

Multiplying(2) by 3 24x-15y=0

30x-15y-24x+15y=300

6x=300,x=50

6×50-3y=60

300-3y=60

-3y=60-300=-240

Y=80

The product of the strength of two groups=50×80=4000.

**Question-4****Explanation**

** Laurel and Hardy Company dealing in export of granite stones employs 500 people – men and women who have all qualified in engineering education. The average salary of all the staff in Laurel and Hardy company is Rs. 5000. The average salary of the officers is Rs. 14000 and that of the rest is Rs.4000. Identify the number of officers in this company.**

**Options :**

a)40

b)80

c)50

d)70

**Answer: c) 50 **

Let the number oof officers be x

It is given that the average salary of officer is Rs. 14000

So total salary paid to officers will be 14000x.

Number of staff other than officers=500-x

So—14000x+(500-x)4000=500×5000=25000000

14000x+2000000-4000x=25000000

10000x=2500000-2000000=500000

Therefore x=50.

**Question-5****Explanation**

**Arihant Apartment has a big cistern fitted with three pipes and let us name them P,Q and R. Pipes P and q can fill it in 3 and 4 hours respectively. Pipe R can empty the cistern in one hour. One day the cistern was cleaned completely and made empty. Then the pipes are opened at 3 am, 4am and 5am respectively on the same day, can you find out the time at which the cistern will again be empty?**

**Options :**

a)7.12 am

b)7.20 am

c)7.40 am

d)6.40 am

**Answer: a) 7.12 am **

Pipe P is opened at 3 am and Pipe Q is opened at 4 am.

So by 5 am when Pipe R(emptying pipe) is opened the cistern will be

1/3X2+1/4=2/3+1/4=11/12 of cistern

When all the three pipes are connected and run for one hour

1/3 +1/4-1=-5/12 That means if all the three pipes run concurrently 5/12 of the cistern will be emptied.

But when Pipe R(emptying) is also opened and all the three run from 5 am

The time taken to empty 11/12 of the cistern is 5/12—1hour

11/12-?

11/12×12/5=21 /5hours from 5 am

That mean 7 hours and 12 minutes.