The total number of HDDs purchased by females from Shop A on Wednesday and…
2024
The total number of HDDs purchased by females from Shop A on Wednesday and Thursday together is what percent less than the total number of HDDs purchased by males from Shop B on Thursday and Friday together?
Answer: B. 20 — ConceptTo find a subgroup count, multiply the total by the subgroup percentage. If a quantity A is x% less than a quantity B, then x = ((B − A) / B) × 100;…
- A.
18
- B.
20
- C.
22.22
- D.
25
Show answer & explanation
Correct answer: B
Concept
To find a subgroup count, multiply the total by the subgroup percentage.
If a quantity A is x% less than a quantity B, then x = ((B − A) / B) × 100; the comparison base is B.
Application
Females at Shop A on Wednesday: 720 × 40/100 = 288.
Females at Shop A on Thursday: 720 × 60/100 = 432.
Their combined total is 288 + 432 = 720.
Males at Shop B on Thursday: 760 × (100 − 25)/100 = 570.
Males at Shop B on Friday: 550 × (100 − 40)/100 = 330.
Their combined total is 570 + 330 = 900.
Required percentage less = ((900 − 720) / 900) × 100 = (180/900) × 100 = 20%.
Cross-check
Twenty percent of 900 is 180, and 900 − 180 = 720, which matches the first combined total.
Therefore, the required percentage is 20%.