Question

16) Alberto bought 10 books for a total of $650.

Math books cost $50 and science books cost
$80. How many of each type of book did he
buy?

Answer 1

Answer:
5 math books
5 science books

Let’s say math books are a in this equation and science books are b.
50a+80b= 650
a+b= 10
a=10-b
50(10-b) +80b=650
500- 50b + 80b= 650
500+ 30b= 650
30b= 150
b=5

Then go back to the equation a+b=10
b=5
a+ 5= 10
a=5

Double check the math:
Math books: 50*5=250
Science books: 80*5=400
400+250=650
Which is equal to total given in problem.

Answer 2

he bought 5 math books that are 250 and 5 for science which is 400 add 250 and 400 and get 650 hope this helps!