Dear reader here we are providing some question on

mathematics which can be helpful in your upcoming CTET exam.

mathematics which can be helpful in your upcoming CTET exam.

**1.**

A certain sum at a

simple interest amounts to Rs 1350 in 5 year and to Rs.1620 in 8 year. What is

the sum

(a)

700

(b) 800

700

(b) 800

(c)

900

(d) 1000

900

(d) 1000

**2.**

The compound interest on

a certain sum of money for 20 years at 10% per annum is Rs. 420. Find the

simple interest at the same rate and for the same time.

(a) Rs.

400

(b) Rs. 500

400

(b) Rs. 500

(c) Rs. 450

(d) Rs. 550

(d) Rs. 550

**3.**

A sum of money amounts to

Rs 500 in 2 year and Rs 540 in 3 years at compound interest per annum , then

the rate of interest per annum is

(a)

6%

(b) 7%

6%

(b) 7%

(c)

8%

(d) 10%

8%

(d) 10%

**4.**

The simple interest

accrued on an amount of Rs. 25,000 at the end of three years is Rs. 7,500. What

would be the compound interest accrued on the same amount at the same rate in

the same period?

(a) Rs. 7,750

(b) Rs.

8,275

(b) Rs.

8,275

(c) Rs. 8,500 (d) Rs. 8,250

**5.**

In the new budget , the

price of kerosene oil rose by 25%. By how much percent must a person reduce his

consumption so that his expenditure on it does not increase ?

(a)

20% (b) 30%

20% (b) 30%

(c)

22%

(d) 24%

22%

(d) 24%

**6.**

The value of a machine

depreciates at the rate of 10% per annum. If its present is Rs.1,62,000.? What

was the value of the machine 2 years ago ?

(a)

200000 (b) 20000

200000 (b) 20000

(c)

2000

(d) None of these

2000

(d) None of these

**7.**

A student multiplied a

number by 3/5 instead of 5/3. What is the percentage error in the calculation?

(a)

60%

(b) 62%

60%

(b) 62%

(c)

64%

(d) 65%

64%

(d) 65%

**8.**

The average age of 40 boys in a class is 15.

The average age of a group of 18 boys in the class is 16 and the average age of

another12 boys in the class is 14. What is the average age of the remaining

boys in the class?

(a) 15·25 years (b) 14.4years

(c) 14·75 years (d) None of these

**ANSWERS WITH EXPLANATION:**

**1.**

**(c):**

Amount in 5 years = 1350

Amount in 8 year = 1620

Interest for three year = 1620-1350 = 270

Interest for one year = 90

Interest for 5 year = 90*5 =450

Sum = 1350 – 450 = 900

2.

**(a):****Solve this question with**

help of formula

SI=[200r/ r(r+200)]*CI

SI=200*10*420/10*210 = Rs. 400

3.

**(c):**
The rate% = difference of amounts*100 /first amount

= (540-500)*100/500,

= 40*100/500 = 8%

4.

**(b):****Rate =7500*100 / 25000*3 = 10% p/a**

CI= 2500[{1+ (10/100)} 3-1]

=25000* [1.331-1]=25000*.331= Rs. 8,275

**5.**

**(a) :**

Reduction in consumption = [((R/(100+R))*100]%

? [(25/125)*100]%=20%.

? [(25/125)*100]%=20%.

**6.**

**(a):**

Value of the machine 2 years ago

= Rs.[162000/(1-(10/100)2)]=Rs.[162000*(10/9)*(10/9)]= Rs.200000

= Rs.[162000/(1-(10/100)2)]=Rs.[162000*(10/9)*(10/9)]= Rs.200000

**7.**

**(c) :**

Let the number be x

Then, error =

(5/3)x – (3/5)x =(16/15)x

(5/3)x – (3/5)x =(16/15)x

Error% = [(16x/15)

/(5x/3)] * 100% = 64%

/(5x/3)] * 100% = 64%

**8.**

**(b):**

Total students are 40×15=600

So, 18 x 16 +(12+14)= 456

Left student is 10 and their average is

=600-456= 144÷ 10=14.4

=600-456= 144÷ 10=14.4