Problem-Solving and Data AnalysisHardOriginal value before two percent changes
Problem-Solving and Data Analysis practice question
A number is increased by 20 percent, and the result is then decreased by 25 percent, giving 90. What was the original number?
Answer: 100
1.20 × 0.75 = 0.90, so 0.90x = 90 and x = 100.
Common wrong answers
- If you answered 90
- 90 assumes the changes cancel.
- If you answered 95
- 95 adds 5 percent, the difference of the percents.
- If you answered 120
- 120 applies only the increase.
More Problem-Solving and Data Analysis questions
- Hard
The mean of five numbers is 12. If four of them are 8, 10, 14, and 16, what is the fifth number? - Hard
In a survey of 50 people, 30 like coffee, 20 like tea, and 8 like both. How many like neither? - Hard
A car travels at 60 mph for 2 hours, then 40 mph for 3 hours. What is its average speed for the whole trip? - Hard
Which statement correctly compares the standard deviations of the two sets? - Hard
Which statement best interprets the slope of the line of best fit? - Hard
How many milliliters of the 40% acid solution must the chemist add?
Not affiliated with the College Board. SAT is a trademark of the College Board.