In a printing press, 12 men and 16 boys finish a binding job in 5 days, while 13 men and 24 boys finish the same job in 4 days. The ratio of the work done in a day by one man to that done in a day by one boy is:

The same job is done either way, so $5(12m+16b)=4(13m+24b)$ → $60m+80b=52m+96b$ → $8m=16b$, giving $m:b=2$ : 1. A man does twice a boy's work. (The second team has one extra man and eight extra boys and finishes a day sooner — comparing head-counts alone, 28 against 37, tempts the answer 1 : 2 with the ratio upside down.)