A school has received 60% of the amount it needs for a new building by receiving a donation of $400 each from people already solicited. People already solicited represent 40% of the people from whom the school will solicit donations. How much average contribution is requited from the remaining targeted people to complete the fund raising exercise? Choose one:
A) $200
B) $177.78
C) $100
D) $277.78
E) $377.78
Let us suppose there are 100 people. 40% of them donated $16000 ( 400 * 40 )   $16000 is 60% of total amount.   So total amount = 16000 * 100/60   Remaining amount is 40% of total amount.   40% of total amount = 16000 * (100/60) * (40/100) = 32000/3   This amount has to be divided by 60 ( remaining people are 60 )   So per head amount is 32000/3 / 60 = 32000/180 = 1600/9 = $177.78;   ANSWER:$177.78
<result>B</result>
A school has received 60% of the amount it needs for a new building by receiving a donation of $400 each from people already solicited. People already solicited represent 40% of the people from whom the school will solicit donations. How much average contribution is requited from the remaining targeted people to complete the fund raising exercise?