21. Exercise problems XIV

A $1.2 m$ tall girl spots a balloon moving with the wind in a horizontal line at a height of $88.2 m$ from the ground. The height of $88.2 m$ from the ground. The angle of elevation of the balloon from the eyes of the girl at any instant is $60^°$. After some time, the angle of elevation reduces to $30^°$ (see Fig.). Find the distance traveled by the balloon during the interval.

 

Distance travelled by the balloon $=$ $m$