Answer:
24
Explanation:
Zara ate 25% of the cookies.
100% - 25% = 75%
Zara left 75% of the cookies.
Her cousin ate 18 cookies.
That means that 75% of the cookies is 18 cookies.
Let x = original number of cookies.
75% of x = 18
0.75x = 18
Divide both sides by 0.75
x = 18/0.75
x = 24
Answer: 24