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Mike spent $410 on books. Math books cost $80, and science books cost $50. If he bought a total of 7 books, how many of each kind did he buy?

A. Math books
B. Science books

1 Answer

3 votes

Final answer:

Mike bought 2 math books and 5 science books.

Step-by-step explanation:

Step 1: Let's assume Mike bought x math books and y science books. We can create the following equations:
x + y = 7 (since he bought a total of 7 books)
80x + 50y = 410 (since he spent a total of $410)

Step 2: We can solve these equations using substitution or elimination.
For substitution, we can solve the first equation for x:
x = 7 - y
Substituting this value of x into the second equation:
80(7 - y) + 50y = 410
560 - 80y + 50y = 410
-30y = 410 - 560
-30y = -150
y = (-150)/(-30) = 5

Step 3: We can plug the value of y back into the first equation to find x:
x + 5 = 7
x = 7 - 5
x = 2

Step 4: Therefore, Mike bought 2 math books (option A) and 5 science books (option B).

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