## Ques 1.

Ravi goes downstream 120 km and upstream 40 km, taking 4 hrs each. What is the speed of current?

Down stream speed = 120/4 = 30 kmph

Up stream speed = 40/4 = 10 kmph

Speed current = (30-10)/2 = 10 kmph

## Ques 2.

Three buses travel same distance with speeds in the ratio 3 : 4 : 5. What is the ratio of the times taken by them to cover the distance?

**Solution :**

Time ratio = 1/3 : 1/4 : 1/5

==> Ratio = 20 : 15 : 12

## Ques 3.

Chocolates are bought at 54 for a rupee. How much must be sold for a rupee so as to gain 50%?

**Solution :**

= 54 * 100/150

= 36

## Ques 4.

A bag contains 6 red and 4 blue balls. 2 balls are drawn one by one without replacement. What is the probability that the balls are alternately of different colors?

**Solution :**

**When 1st is red = 6/10 * 4/9 = 12/45**

When 1st is green = 4/10 * 6/9 = 12/45

When 1st is green = 4/10 * 6/9 = 12/45

Add two cases = 24/45 = 8/15

## Ques 5.

Three pipes A, B and C can fill the tank in 10, 20 and 30 minutes respectively. If all the pipes are opened together and pipe B is turned off 5 minutes before the tank is fill. Then find the time in which the tank will full.

Solution :

Let total time taken by the pipes is T hrs, then

==> (1/10 + 1/20 + 1/30)*(T – 5) + (1/10 + 1/30)*5 = 1

==> (1/10 + 1/20 + 1/30)*(T – 5) + (1/10 + 1/30)*5 = 1

==> (11/60)*(T-5) +(4/30)*5 = 1

==> T = 75/11

## Ques 6.

If the price of sugar is reduced by 10%. How many kilograms of sugar a person can buy with the same money which was earlier sufficient to buy 50 kg of sugar ?

**Solution :**

**Let the original price = 100 Rs per kg**

Then money required to buy 50 kg = 50*100 = Rs 5000

New price per kg is (100-90)% of Rs 100 = 90

So quantity of sugar bought in 5000 Rs is 5000/90 = 55.55 kg

Then money required to buy 50 kg = 50*100 = Rs 5000

New price per kg is (100-90)% of Rs 100 = 90

So quantity of sugar bought in 5000 Rs is 5000/90 = 55.55 kg

## Ques 7.

A Company makes a profit of Rs.3,80,000, 10% of which is paid as taxes. If the rest is divided among the partners A, B and C in the ratio 5:3:4 then the share of A is

**Solution :**

**10% = 380000*10/100 = 38000**

Remaining = Rs.3,42,000

X = 3,42,000*3/12 = 85,500Remaining = Rs.3,42,000

X = 3,42,000*3/12 = 85,500

## Ques 8.

What half of a number is added to 468, it becomes five time of itself. What is the number ?

**Solution :**

**x/2 + 468 = 5x**

==>5x – x/2 = 468

==>9x/2 = 468

X = 468*2/9= 104==>5x – x/2 = 468

==>9x/2 = 468

X = 468*2/9= 104

## Ques 9.

Milk contains 40% water. What quantity of pure milk should be added to 150 liters of this milk to reduce the quantity of water to 30%?

**Solution :**

60 100

70

30 10

Ratio = 3 : 1

==> 150/X = 3/1

==> X = 50

## Ques 10.

18 119 708 ? 14136 42405

**Solution :**

**18*7 -7 = 119**

119*6 -6 = 708

708*5 -5 = 3535