Mathematical Aptitude - Ratio Proportion, Percentage and Discounting

Avatto>>UGC NET PAPER 1>>PRACTICE QUESTIONS>>Mathematical Aptitude>>Ratio Proportion, Percentage and Discounting

11. If A’s income is 25% more than B’s, and B’s income is 20% more than C’s, then by what per cent is A’s income more than C’s?

  • Option : D
  • Explanation : Let C’s income = 100
    B’s income = 100 + 20 = 120
    A’s income = 125% of 120 = 150
    Thus, A’s income is 50% higher than that of C.
Cancel reply
Cancel reply

12. A dealer marks his goods 20% above the cost price. He then allows some discount on it and makes a profit of 8%. The rate of discount is

  • Option : C
  • Explanation : Let cost price = 100
    Net selling price = 100 + 8 = 108
    Now 120 – (x% of 120) = 108
    x = 10
Cancel reply
Cancel reply

13. As the price of mangoes decreased by 25%, I can purchase 4 mangoes more for Rs 60. What is the new price of one mango?

  • Option : C
  • Explanation : Discount on Rs 60 = 25% of Rs 60 = Rs 15
    Assume that the retailer offers a discount of Rs 15 or 4 extra mangoes.
    New purchase price of 4 mangoes = Rs 15
    Purchase price of one mango = 15/4 = Rs 3.75
Cancel reply
Cancel reply

14. If the length of a rectangle increases by 10%, then by what per cent should the breadth decrease to maintain the same area?

  • Option : C
  • Explanation : Suppose both length and breadth are 100.
    Hence, area = 100 × 100
    New length = 100 + 10 m = 110
    As area is to be kept same,
    110 × new breadth = 100 × 100
    New breadth = 100 × 100/110 = 1000/11
    Decrease in breadth = 100 − 1,000/11 = 100/11 = 9.11%
    As breadth was assumed to be 100, no additional calculation is required for percentage figure.
Cancel reply
Cancel reply

15. If the price of potatoes increased first by 20% and subsequently by 40%, then what is the final price per kilogram if the original price was Rs 25 per kg?

  • Option : B
  • Explanation : Using the formula: x + y + xy/100, net percentage increase = 20 + 40 + (20 × 40)/100 = 68%
    Increased price = Rs 25 + 68% of 25 = 25 + 17 = Rs 42
    Alternatively: Using the multiplier factor concept, we get the final price as 25 ×[6/5]x[7/5]=Rs 42
Cancel reply
Cancel reply