<PRE><B>Question 1020539</B>
Hi there,
1)  B varies jointly with m and n
B = kmn (Where k is the constant of proportionality.)
2)A farmers harvest in bushels varies directly with 
the number of acres planted.
B = kn (Where k is the constant of proportionality.)
To find k:
Using  8 acres can produce 144 bushels
B = kn
144 = k8
k = 144/8
k = 18
Formula:
B = 18n
Problem
B = 18n
1152 = 18n
n = 1152/18
n = 64 acres.
Hope this helps :-)

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