Directions: Each of the questions given below is followed by series of options among which you have to choose the best one. You can also review your choices by clicking into answer section.
1. A man spends one-fifth of his salary for household expenditures and one fourth of the remaining for his children. He donates one-third of what is left to charity and saves the rest. If he saves Rs.20000, find his salary.
A. Rs.100,000
B. Rs.50000
C. Rs.80,000
D. Rs.60,000
Answer
Explanation:
Let his salary be Rs.x
Amount spent for household expenditures = x/5
Amount spent for children =(1/4)*(4x/5) = x/5
Amount left = x-(2x/5) = 3x/5
Amount donated to charity = (1/3)*(3x/5) = x/5
Amount left =Amount saved
x-(3x/5) = 20000
2x/5 = 20000
x=Rs.50000
2. By how much is one-third of 570 lesser than half of 450?
A. 60
B. 45
C. 30
D. 35
Answer
Explanation:
(1/3)*570 = 190
(1/2)*450 = 225
Then, 225-190=35
3. 60% of a class is boys and 40% are girls. 30% of the girls and 50% of the boys went for a trip. What fraction of the class didn't go for the trip?
A. 29/50
B. 21/50
C. 31/50
D. 19/50
Answer
Explanation:
Let the no. of students in the class be x.
No. of students who went for the trip
= 30% of 0.4x + 50% of 0.6x
=> 0.12x+0.3x
=> 0.42x 0.58x
Students did not go for the trip. 0.58x/x => 58/100
=> 29/50
4. Shyam spends one-fifth of his salary for his children's education, 20% for household expenditures, 10% for other miscellaneous expenses and saves the rest. What fraction of his salary does he save?
A. 1/2
B. 2/5
C. 1/4
D. 3/5
Answer
Explanation:
No explanation
5. A box contains 140 ice-creams, 30% of which are strawberry, two-sevenths are chocolate, 5% are mango and the rest are vanilla. How many ice-creams are vanilla flavoured?
A. 14
B. 49
C. 35
D. 51
Answer
Explanation:
No. of strawberry ice-creams = 30% of 140 = 42
No. of chocolate ice-creams = (2/7)*140 = 40
No. of mango ice-creams = 5% of 140 = 7
No. of vanilla = 140-(42+40+7) = 51
6. If x=1/y and y=1/z, then
A. x=1/z
B. x=1/z²
C. x=z
D. None of the above
Answer
Explanation:
x=1/y
x=1/(1/z)
= z
7. If a=(3/7), b=(3/7)2; and c=?(3/7), then which of the following is true?
A. b<a<c
B. b<c<a
C. c<a<b
D. a<c<b
Answer
Explanation:
Squaring a proper fraction will make it smaller.
=> (3/7)² = 9/49
Compare 3/7 and 9/49
3/7 = 21/49
9/49<21/49
(3/7)²<3/7<?(3/7) b<a<c
8. The sum of a number and its reciprocal is 17/4. Find the number.
A. 8
B. 6
C. 10
D. 4
Answer
Explanation:
Let the number is x
x+(1/x) = 17/4
(x²+1)/x = 17/4
Substitute the options in the above equations. x=4
9. If x=5 and y=7, find the value of (x2-14x+49)/(25-10y+y2 )
A. 1
B. 2
C. 3
D. 4
Answer
Explanation:
(x²-14x+49)
= (x-7)²
= (5-7)²
= 4
Then, (25-10y+y²)
= (5-y)²
= (5-7)²
= 4
Hence, (x2-14x+49)/(25-10y+y2 ) = 4/4 = 1
10. Find the decimal value of 30% of 20% of (7/12).
A. 0.7
B. 0.07
C. 0.035
D. 0.35
Answer
Explanation:
(30/100)*(20/100)*(7/12) = 7/200 = 0.035
11. If x=2 and y=3, find the value of x+(1/x)+(1/y)+y
A. 35/6
B. 6
C. 5/2
D. 7/2
Answer
Explanation:
x+(1/x)+(1/y)+y
= 2+(1/2)+3+(1/3)
= 35/6
