Question

By the age of five, a child's brain reaches ________ per cent of its full weight...​

Answer 1

$\huge\boxed{\fcolorbox{white}{pink}{:) 90 per cent}}$

Answer 2

Answer:

90% of Brain Growth Happens Before Kindergarten

At birth, the average baby's brain is about a quarter of the size of the average adult brain. Incredibly, it doubles in size in the first year. It keeps growing to about 80% of adult size by age 3 and 90% – nearly full grown – by age 5.