A number is increased by 40% to give 91. What was the original number?
Answer and explanation
Correct answer: D. 65
- Step 1: An increase of 40% means the original is multiplied by 1.4. Step 2. Reverse it: 91 ÷ 1.4 = 65. Answer: 65. Why not the others: 51: This subtracts 40 from 91 as if 40% were a fixed amount. 127.4: This increases 91 by 40% again. 54.6: This takes 40% off 91 instead of dividing by 1.4.
Practise more Algebra, ratio and problem solving.
Free questions with an explanation for every one, and full timed Independent School Entrance (ISEB Pre-Test and 11+ CEM style) mock tests.
More Algebra, ratio and problem solving questions
- Solve 4(2x - 3) = 3x + 13.
- Three consecutive odd numbers add up to 99. What is the largest of them?
- If a = 3 and b = -2, what is the value of a² - 2ab + b²?
- The first terms of a sequence are 7, 11, 15, 19. What is the 50th term?
- The ratio of boys to girls in a club is 3 : 5. When 6 more boys join, the numbers of boys and girls are equal. How many members were in the…
- Pasta is sold in three packs: 750 g for £1.80, 500 g for £1.15 and 1.2 kg for £2.64. Which pack is the cheapest per 100 g?