Mathematics for IGCSE & O level - Proportion (Section 2 - No. 49)
The number of days to complete a project is inversely proportional to the number of workers. If 10 workers can complete a project in 14 days, how many days will it take 7 workers to complete the same project?
7
10
14
20
Giải thích
Let the number of workers by x and the number of days by y. xy= constant value. The constant value = 10*14 = 140. 7*y = 140; y=20.