Exercise 4 Page 159

We know that 3 cups of peaches make 4 jars of peach-only jam. Using this information, we can write a ratio. 3 Cups of peaches/4 Jars of peach jam Let's assume, for a moment, that Jim is making 10 jars of peach-only jam. The ratio will be equal to the ratio of cups of peaches to 10 jars of jam. If we let p represent the total number of cups of peaches needed to make 10 jars of peach jam, we get the following proportion. 3/4=p/10By solving for p, we will find the number of cups of peaches required to make 10 jars of jam, so let's do that.

3/4=p/10

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Solve for p

CrossMult

Cross multiply

30=4p

RearrangeEqn

Rearrange equation

4p=30

DivEqn

.LHS /4.=.RHS /4.

p=30/4

ReduceFrac

a/b=.a /2./.b /2.

p=15/2

CalcQuot

Calculate quotient

p=7.5

Jim needs a total of 7.5 cups of peaches to make 10 jars of jam. If Jim uses equal amounts of peaches and strawberries to make his strawberry-peach jam, he only needs half of this amount of peaches. p=7.5cups/2 Because the amount of peaches and strawberries are equal in this jam, we should substitute p with a variable to represent the strawberries. Let's use s. s=7.5cups/2 Now we can calculate the number of cups of strawberries Jim needs for his strawberry-peach jam.

s=7.5/2

WriteDec

Write as a decimal

s=3.75

Rewrite

Rewrite 3.75 as 3 34

s=3 34

Jim needs 3 34 cups of strawberries, which corresponds to option F.