Answer: he watched 1/12 of the movie at night.
Step-by-step explanation:
Let x represent how much of the movie that he watched at night.
Tanner watched 1/4 of a movie in the morning, and he watched some at night. This means that she had already watched
x + 1/4 = (4x + 1)/4 of the movie by the end of the day. Therefore, what he has left to watch would be
1 - (4x + 1)/4 = [4 - (4x + 1)]/4
= (3 - 4x)/4
By the end of the day, he still had 2/3 of the movie to watch, it means that
(3 - 4x)/4 = 2/3
Cross multiplying, it becomes
3(3 - 4x) = 4 × 2
9 - 12x = 8
12x = 1
x = 1/12
