Question

Kymbrea's comic book collection currently has $30$ comic books in it, and she is adding to her collection at the rate of $2$ comic books per month. LaShawn's collection currently has $10$ comic books in it, and he is adding to his collection at the rate of $6$ comic books per month. After how many months will LaShawn's collection have twice as many comic books as Kymbrea's?

$1$

$4$

$5$

$20$

$25$

Answer: E

Concepts:linear equation

Difficulty rating: 920

Solution:

After $m$ months, Kymbrea has $30 + 2m$ comic books and LaShawn has $10 + 6m.$ Setting $10 + 6m = 2(30 + 2m)$ gives $10 + 6m = 60 + 4m,$ so $2m = 50$ and $m = 25.$

Thus, the correct answer is E.

2017 AMC 12B Problem 1

Answer: E

Difficulty rating: 920

Solution:

Problem 1 in Other Years