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Whats a Plough?

If 16 horses can plough 1280 acres in 8 days,
how many acres can 12 horses plough in 5 days?

Solution:

Suggested Solution (Bobby Gohl & Michael Mills, WWU students)

H = horses, A = acres, D = days

16H * 12D = 1280A

16H = 160 A/D

H = 10 A/D

12H = 120 A/D

12H * 5D = 600 A

In words, if 16 horses can plow 1280 acres in 12 days, then the same 16 horses can plow 160 acreas/day, and 1 horse can plow 10 acres/day.

If you have 12 horses, then you can plow 120 acres/day, and if you plow for 5 days, then you plow 600 acres.

Source: Charles Pendlebury's Arithmetic (London: G. Bell & Son, 1918)