20 men can build a wall in nine days, then how long would it take 12 m

1.	20 men can build a wall in nine days, then how long would it take 12 men to buildthe same wall?
Answer» One way to look at it is as an indirect ratio (if I recall the term correctly, it's been over 50 years) . 20 men times 9 days equals 12 men times X. So, if 20×9=180 then 12×X=180 Dividing 180 by 12 = 15 It would take 15 days 20 men =9 days1 man can take 220×9=180 daysso 12 man can take 180/12=15 daysto build the same wall.

20 men can build a wall in nine days, then how long would it take 12 men to buildthe same wall?

Answer»

One way to look at it is as an indirect ratio (if I recall the term correctly, it's been over 50 years) .

20 men times 9 days equals 12 men times X.

So, if 20×9=180 then 12×X=180

Dividing 180 by 12 = 15

It would take 15 days

20 men =9 days1 man can take 220×9=180 daysso 12 man can take 180/12=15 daysto build the same wall.