Answer:
8 months
Explanation:
The question asks for the minimum number of months it would take her to grow her hair ATLEAST 16 cm.
Lets solve this!
Her hair is ALREADY 4 cm
She needs to make it 16 cm or greater
That is:
16 - 4 = 12 cm MORE
Per month growth rate = 1.5 cm
So we will divide the amount she needs to grow (atleast) by the growth rate per month:
12/1.5
= 8
Thus, in 8 months, her hair will grow:
8 * 1.5 = 12 cm
and 4 cm from before, so
12 + 4 = 16 cm
So, it will take a minimum of 8 months