Susan can type 10 pages in 5 minutes. Mary can type 5 pages in 10 minutes.…
2023
Susan can type 10 pages in 5 minutes. Mary can type 5 pages in 10 minutes. Working together, how many pages can they type in 30 minutes?
- A.
15
- B.
20
- C.
25
- D.
65
Attempted by 18 students.
Show answer & explanation
Correct answer: D
Correct approach:
Susan's rate: 10 pages in 5 minutes → 10 ÷ 5 = 2 pages per minute. In 30 minutes she types 2 × 30 = 60 pages.
Mary's rate: 5 pages in 10 minutes → 5 ÷ 10 = 0.5 pages per minute. In 30 minutes she types 0.5 × 30 = 15 pages.
Together: 60 + 15 = 75 pages in 30 minutes.
Final answer: 75