We can solve this problem by the rule of three.
A complete pie chart has 360º.
45º----------------------6 people
360º-------------------- x
x=(360º*6 people) / 45º=48 people.
Answer; 48 people.
36,00÷ 12= 3,000 so that would be the average monthly loss.
9 dived by 3 = 3
so he surfed for 3 hours = 1/3 of 9
and there are 6 hours left
so he spent 6 hours building a sandcastle