Amanda bought diaries at $3 each and sold them at $8 each. Customers who bought 2 diaries frome her were given one diary free. At the end of the sale, Amanda made a profit of $1235 even after giving away 150 copies of diaries free.Assuming that the customers either bought 1 or 2 diaries each time, find the number of customers who had bought only one diary?请解释清楚！
热心网友
赠送出150本日记。说明有150名顾客以8美圆/本买了2本。从这些顾客获得销售额 150*2*8=2400美圆而资本为 150*3*3=1350美圆从这150名顾客获得的利润2400-1350=1050美圆总利润1235美圆1235-1050=185美圆这185美圆来自 以1本日记形式卖出时 获得的利润每本的利润为5美圆185/5=37 即有37名顾客买了1本日记。
热心网友
[1235－150×（8×2－3×3）]÷（8－3）＝37The answer is 37.
热心网友
(8x+150*2*8)-3(x+3*150)=1235x=37The number of customers who had bought only one diary is 37.