The Percentage $p ( t )$ Of Children Who Are Able to Speak in at Least

Multiple Choice

The percentage $p ( t )$ of children who are able to speak in at least single words by the age of t months can be approximated by the equation.
$p ( t ) = 100 \left( 1 - \frac { 12,188 } { t ^ { 4.42 } } \right)$
By what age are 70% of children speaking in at least single words Round your answer to the nearest month.

A) 16
B) 7
C) 11
D) 5
E) 8