The painting rate for 10 people is:
10/5
The painting rate for 7 people is:
7/5
Now use the rule of 3:
10/5 → 100%
7/5 → x
(7/5 * 100) / 10/5
140 / 10/5
140 / 2
70
Answer:
70% of the building can be painted by 7 men in 5 days.
Hope it helped,
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