Math Problem, Systems of Equations

Question

The time,t, in hours that it takes x people to bake n pies varies directly with the number of pies and inversely with the number of people. Suppose 6 people can bake 12 pies in 3 hours. How many people are needed to bake 28 pies in 5.25 hours

Answer 1

t = n/p (k)

 

3 = 12/6 (k)

3 = 2k

3/2 = k

 

5.25 = (28/p) (3/2)

5.25 = (28 · 3)/2p

2p · 5.25 = 84

5.25p = 42

8 = p 

 

To bake 28 pies in 5.25 hours you need 8 people.