Question 17
MediumOriginal questionVarun can dig a garden bed in 10 days and Lakshmi in 15 days. They start together, but Varun stops 5 days before the digging is finished and Lakshmi completes it. How many days does the digging take in all?
Show the answer and explanation
CorrectNot quiteAnswer C
Correct answer: C
Explanation
Let the total be days. Lakshmi works all days; Varun works .
. Multiply by 30: .
, so days.
Worth noting
8 days comes from letting the wrong person stop early. 11 days wrongly adds the 5 days to the together time of 6 days.
- Concept
- Worker leaving a fixed number of days before completion
- Typical timeTypical
- 70 s
- Your timeYours
- —
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Ten questions from Time & Work, at your own pace.