Q: 1 Since prices of mangoes decreased by 25%, I can purchase 4 mangoes more for Rs. 60. What is the original price of one mango?
ANS : (d)The equation for this would be 60/(0.75x)-60/x=4 where x is the original price of
Alternately, since prices decreased by 25%, had I purchased the same number of mangoes as earlier, I would have saved 25% of 60, i.e. Rs. 15. This means that in Rs. 15 I can get 4 mangoes at new rate
∴New rate=15/4 Old rate=15/4×4/3=Rs.5
Q: 2 If the price of potatoes increased first by 20% and subsequently by 40%. What is the final price per kilogram, if the original price was Rs. 25 per kilogram?
ANS : (a) Using the fraction method, we get the final price as 25×(6/5)×(7/5)= Rs.42
Q : 3 5% of income of A is equal to 15% of income of B and 10% of income of B is equal to 20% of income of C. If income of C is Rs. 2,000, then total income of A, B and C is
(5/100) A=(15/100) B and (10/100) B=(20/100) C
∴A=3B and B=2C=2×2000=4000
A + B + C = (12000 + 4000 + 2000) = 18000
Q: 4 An amount kept at CI, earns an interest of Rs. 600 in the 7th year and an interest of Rs. 660 in the 8th year. Find the rate of interest.
ANS : (a) The interest is higher in the 8th year by Rs. 60 and this amount should be equal to the interest on the 7th year’s interest i.e. Rs. 600. Thus the rate of interest = 10%
Q : 5 The rate of interest on a sum of money is 4% p.a. for the first 2 years 6% p.a. for the next 3 years and 8% p.a. for the period beyond 5 years. If the simple interest accrued by the sum for a total period of 8 years is Rs. 1,280 then what is the sum ?
ANS : (d) Let the sum be Rs. x. Then,
=1280 or 50x=1280 x 100
Q: 6 The rates of simple interest in two banks A and B are in the ratio 5 : 4. A person wants to deposit his total savings in two banks in such a way that he receives equal half yearly interest from both. In what ratio, he should deposit his savings in banks A and B?
Ans(c) : Let the savings be X and Y and the rates of simple interest be 5x and 4x respectively.
X × 5x×(1/2)×(1/100)
= Y ×4x ×(1/2)×(1/100) or
i.e. X : Y = 4 : 5
Q : 7 Mr. Kuber bought a flat in Swarg Lok Apartments for $1,000. What would the future value( in $) of the flat after 2 years if the value is compounded semi – annually at 22% per annum?
ANS : (c) Future value = Present value
Here r = semi-annual rate of interest = 22/2=11%,
n = Number of time periods = 2 × 2 = 4.
Q : 8 An off-season discount of x% is being offered at the discount store. An additional 12.5% discount is given if the value of purchase is more than Rs. 500. After the discounts, a person pays Rs. 525 for a jean whose list price is Rs. 750. Find the value of x.
ANS : (a)
Final selling Price = Rs. 525
Hence, x = 20%
Q: 9 Vivek purchased 120 tables at a price of Rs. 110 per table. He sold 30 tables at a profit of Rs. 12 per table and 75 tables at a profit of Rs. 14 per table. The remaining tables were sold at a loss of Rs. 7 per table. What is the average profit per table ?
ANS : (a) Total C. P. = Rs. (120 ×110) = Rs. 13,200
Total S.P. = (30 ×110 + 30 × 12) + (75 ×110 + 75 ×14) + (15 ×110 –15 × 7) = Rs. 14,505
Average profit = Rs. ((14505-13200)/120)=Rs.1305/120=Rs.10.88
Q : 10 A trader has a weighing balance that shows 1,200g for a kilogram. He further marks up his CP by 10%. Find the net profit
ANS: (c) Due to defect in weighing balance initially there is a profit of 20%.
Now there is a mark-up of 10% in CP.
Therefore, net profit = 10+20+(10×20)/100=32% profit.