RRB NTPC - Simple Interest

1.

A borrow took by a man, for every 5 years it will be doubled, then what is the rate of the interest? 

   A.) 15%
   B.) 20%
   C.) 22%
   D.) 23%

Answer: Option 'B'

P = 1 , I = 1 , T = 5years R = ? 
I = PTR/100 
1 = 1×5×R/100 
R = 20% 

2.

In how many years will sum of Rs.6000/- yield an interest of Rs.1200/- at 8% p.a? 

   A.) 2 1/2 years
   B.) 2 years
   C.) 1 1/2 years
   D.) 3 years

Answer: Option 'A'

P = Rs.6000/- 
T = ? 
R = 8% 
I = Rs.1200/- 
I = PTR/100 
T = (I × 100)/PR 
T = (1200 × 100)/(6000 × 8) 
T = 5/2 ==> 2 1/2 years 

3.

A borrow took by a man, for every 12 years it will be 5 times, then what is the rate of the interest?

   A.) 33 1/3%
   B.) 18 1/3%
   C.) 33 2/3%
   D.) 34%

Answer: Option 'A'

P = 1 , I = 4 , T = 12years R = ? 
I = PTR/100 
4 = 1×12×R/100 
R = 33 1/3% 

4.

A man took some money for borrowed, for 3 years the total will be Rs.4000 and 5 years it will be Rs.5000/-. Then how much amount he borrowed? 

   A.) Rs.500/-
   B.) Rs.1500/-
   C.) Rs.2500/-
   D.) Rs.1000/-

Answer: Option 'C'

3 years --------> Rs.4000/- 
5 years --------> Rs.5000/- 
~                    ~
------------------------------  
2 years ----> Rs.1000/- 
1 year  -----> Rs.500/-  
3 years × Rs.500/- = Rs.1500/- 
P = Rs.4000/- - Rs.1500/- = Rs.2500/- 
P = Rs.2500/-

5.

Find simple interest on Rs.5000/- at 12% p.a. for 73days? 

   A.) Rs.220/-
   B.) Rs.120/-
   C.) Rs.210/-
   D.) None of these

Answer: Option 'B'

73 days = 73/365 = T 
P = Rs.5000 
R = 12% 
I = (5000*73/365*12)/100 = 120/- 
I = Rs.120/- 

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