Question

A cookie recipe calls for 7/6 of a cup of flour and makes 3 dozen cookies. If Cassandra plans to make 21 dozen cookies, how many cups of flour does she need?Cassandra needs ____ cup(s) of flour.(Simplify your answer.)

Answer 1

Given that:

- The recipe calls for this amount of flour for 3 dozen cookies:

`(7)/(6)cup`

- Cassandra plans to make 21 dozen​ cookies.

Let be "x" the number of cups of flour she needs to make 21 dozen​ cookies.

Using the data given in the exercise, you can set up the following proportion:

`((7)/(6))/(3)=(x)/(21)`

Now you have to solve for "x":

1. You can rewrite the expression on the left side as follows:

`(7)/(6)\cdot(1)/(3)=(x)/(21)`

2. Simplify by multiplying the fractions on the left side:

`(7)/(18)=(x)/(21)`

3. Multiply both sides of the equation by 21:

`\begin{gathered} (7)/(18)\cdot21=(x)/(21)\cdot21 \\ \\ (147)/(18)=x \end{gathered}`

4. You can reduce the fraction by dividing the numerator and the denominator by 3:

`\begin{gathered} (147/3)/(18/3)=x \\ \\ x=(49)/(6) \end{gathered}`

Hence, the answer is:

`(49)/(6)cups`