Question

april bought some sports drinks and slices of pizza for her friends. She bought 3 more sports drinks than slices of pizza. If her total order was 21.25, how many sports drinks did she purchase? one slice of pizza cost 2.25 and one sport drink cost 1.25

Answer 1

Answer: She purchased 8 sports drinks,

Step-by-step explanation:

Let be "d" the number of sports drinks that April purchased and "p" the number of slices of pizza that April purchased.

Set up a System of equations:

$\left \{ {{d=p+3} \atop {2.25p+1.25d=21.25}} \right.$

In order to solve the System of equations you can use the Substitution Method:

1. Solve for "p" from the first equation:

$d=p+3\\\\p=d-3$

2. Substitute it into the second equation:

$2.25(d-3)+1.25d=21.25$

3. Finally, you must solve for "d" in order to find its value. You get that this is:

$2.25(d-3)+1.25d=21.25\\\\2.25d-6.75+1.25d=21.25\\\\3.5d=21.25+6.75\\\\d=\frac{28}{3.5} \\\\d=8$