In
this section those important questions are included, which are
frequently asked in majority of exams. The regular practice of these
questions will substantially improve the confidence of the students,
therefore they could get maximum marks in the exam...
1.
Raju has 31.25 meters of cloth and he has to make 16 pieces out of a meter of cloth. How many pieces can he make out of this cloth?
(a) 300 (b) 400
(c) 520 (d) 500
(e) None of these
Answer: (d) 500
Length of each piece = ( 1/16) m = 0.0625
Required number of pieces = ( 31.25 )
0.0625
= ( 3125 × 100 )
625
= 500
2. The product of two number is 45 and the sum of their squares is 106. The number are:
(a) 9 and 5 (b) 3 and 4
(c) 5 and 19 (d) 45 and 1
(e) None of these
Answer: (a) 9 and 5
Let the number be x and y.
3. The sum of the squares of three consecutive natural number is 2030. What is the middle number?
(a) 25 (b) 26
(c) 27 (d) 28
(e) 32
Answer: (b) 26
Let the number be x, x+1 and x+2.
As given ,
x2+(x+1)2+(x+2)2= 2030
′
3x2+6x–2025= 0
′
x2+2x–675= 0
′
(x+27) (x–25)= 0
x = 25
Middle number = x+1 = 25+1
= 26
4. 3 Men or 5 Women can finish a piece of work in 12 days. How long will 6 men and 5 women take to finish the work?
(a) 4 days (b) 10 days
(c) 15 days (d) 20 days
(e) 17 days
Answer: (a) 4 days
3 Men = 5 Women
6 Men= 10 Women
(6 men + 5 women)= (10 women + 5 women)
= 15 women
M1D1= M2D2
5×12= 15×D2
D2= ( 5×12 ) days
15
= 4 days
5. A sum of money doubles it self in 10 years at simple interest. what is the rate of interest?
(a) 5% (b) 14%
(c) 8% (d) 12%
(e) 10%
Answer: (e) 10%
Let the sum be 100 rs.
After 10 years it becomes 200 rs.
Interest = (200–100) = 100
R= ( 100×100) % = 10%
100×10
6. At what rate percent will the compound interest, does a sum of money become 27 times in 3 years?
(a) 240% (b) 200%
(c) 150% (d) 180%
(e) None of these
Answer: (b) 200%
Required rate percent = 100 [(n)1/t–1] %
= 100 [ (27)1/3–1]
= 100 [ 3–1] %
= 200 %