Question Detail
Evaluate 28% of 450 + 45% of 280
- 232
- 242
- 252
- 262
Answer: Option C
Explanation:
= (28/100) * 450 + (45/100) * 280
= 126 + 126 = 252
1. If sales tax is reduced from 5% to 4%, then what difference it will make if you purchase an item of Rs. 1000
- 10
- 20
- 30
- 40
Answer: Option A
Explanation:
Clue: Answer will be 5% of 1000 - 4% of 1000
2. Rahul's Mathematics test had 75 problems, 10 arithmetic, 30 algebra, 35 geometry problems. Although he answered 70% of arithmetic, 40% of arithmetic and 60% of geometry problems correctly, still he got less than 60% problems right. How many more questions he would have to answer more to get passed
- 5
- 6
- 7
- 8
Answer: Option A
Explanation:
Number of questions attempted correctly = (70% of 10 + 40% of 30 + 60% of 35)
= 7 + 12 + 21 = 40.
Questions to be answered correctly for 60% = 60% of total quations
= 60 % of 75 = 45.
He would have to answer 45 - 40 = 5
3. 10% of inhabitants of a village having died of cholera, a panic set in, during which 25% of the remaining inhabitants let the village. The population is then reduced to 4050. Find the original inhabitants
- 5500
- 6000
- 6500
- 7000
Answer: Option B
Explanation:
Let the total number is x,
then,
(100-25)% of (100 - 10)% x = 4050
=> 75% of 90% of x = 4050
=> 75/100 * 90/100 * x = 4050
=> x = (4050*50)/27 = 6000
4. Out of 450 students of a school, 325 play football, 175 play cricket and 50 neither play football nor cricket. How many students play both football and cricket ?
- 75
- 100
- 125
- 150
Answer: Option B
Explanation:
Students who play cricket, n(A) = 325
Students who play football, n(B) = 175
Total students who play either or both games,
\begin{aligned}
= n(A\cup B) = 450-50 = 400\\
\text{Required Number}, n(A \cap B) \\
= n(A)+n(B)-n(A\cup B) \\
= 325 + 175 - 400 = 100
\end{aligned}
5. In an examination, 34% of the students failed in mathematics and 42% failed in English. If 20% of the students failed in both the subjects, then find the percentage of students who passed in both the subjects.
- 40%
- 42%
- 44%
- 46%
Answer: Option C
Explanation:
Failed in mathematics, n(A) = 34
Failed in English, n(B) = 42
\begin{aligned}
n(A\cup B) = n(A)+n(B)-n(A\cap B) \\
= 34+42-20 = 56 \\
\text{Failed in either or both subjects are 56} \\
\text{Percentage passed = }(100-56)\% \\
= 44\%
\end{aligned}