Q2. In a class of 72 students, 87.5 % of the students cleared the CAT exam. How many did not clear it?
A. 12
B. 9
C. 18
D. None of these
Sol : Option B Explanation: Numbers of students who did not clear the CAT exam = 12.5 * 72/100 = 9.
Q3. The population of a town increases at the rate of 3.7 % each year. It is 31,110 now. What was it last year?
A. 30,000
B. 29,959
C. 30,270
D. None of these
Sol : Option A Explanation: Last year it was x
31110 = x (1 + 3.7/100) ⇒ x = 30000.
Q4. When the cost of cigarettes increases by 25 %, a man reduces his annual consumption by 10 %. Find the % change in his annual expenditure on cigarettes?
A. 12.5 %
B. 11.11 %
C. 15 %
D. 6.25 %
Sol : Option A Explanation: % change in the annual expenditure = 1.25 * 0.9 = 1.125
⇒ Net increase of 12.5 %
5. The tax on an article is increased by 20 %. As a result of which the consumption decreases by 25 %. What is the % change in the tax revenue received by the government from this article?
A. 10 % decrease
B. 15 % increase
C. 10 % increase
D. None of these
Sol : Option A Explanation: % Change in Tax revenue = 1.2 * 0.75 = 0.9
⇒ Net decrease of 10 %.
Q.6. Renuka spends 35 % of her income on clothes and 40 % on food. If food amounts to Rs. 384, what does she spend on clothes (in Rs.)?
A. 436
B. 320
C. 310
D. None of these
Sol : Option D Explanation: Let her total income = x %there4; 40x/100 = 384 ⇒ x = 960.
Hence amount spent on clothes = 960 * 35/100 = 336.
Q.7. Kay required Rs. 800 for paying her fees. She borrowed 20 % from her brother and 30 % of the remaining was funded by her mother. In her bank she had Rs. 200. How much more does she need (in Rs.)?
A. 248
B. 336
C. 148
D. 236
Sol : Option A Explanation: Required amount = 800
From her brother she got = 800 x 20/100 = 160
From her mother she got = (800-160) * 30/100 = 640 * 30/100 = 192
From the Bank she got Rs. 200
∴ Now she needs 800 - (160 + 192 + 200)
= 800 - 552 = Rs. 248 more
Q8. Ali the barber shaved 40 % of his customers and gave a haircut to 80 % of his customers. He charged Rs. 7 for a shave and Rs. 5 for a haircut. If 20 % of customers who opted for a shave also had a hair-cut, what were Khan’s earnings if he had 75 customers (in Rs.)?
A. 410
B. 1,020
C. 510
D. None of these
Sol : Option C Explanation: Total customers = 75
Numbers of customers shaved = 75 * 40/100 = 30
Number of customers who got hair cut = 75 * 80/100 = 60
∴ His total income= (30 * 7) + (60 * 5) = 210 + 300 = 510.