Answer:
Amy can solve 7x math problems in 7 days.
Explanation:
If Amy can solve x problems in one day, we can multiply the number of days by "x" to know how many problems she can solve in this timespan.
Therefore, to determine how many problems Amy can solve in 7 days, we can multiple x by 7.
7 * x = 7x
Therefore, Amy can solve 7x problems in 7 days.