一道简单的英语数学题,An eraser cost 12cents more than a pencil ,12pencils cost 24cents more than than 8erasers.Find the cost 10pencils.

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一道简单的英语数学题,An eraser cost 12cents more than a pencil ,12pencils cost 24cents more than than 8erasers.Find the cost 10pencils.

一道简单的英语数学题,An eraser cost 12cents more than a pencil ,12pencils cost 24cents more than than 8erasers.Find the cost 10pencils.
一道简单的英语数学题,
An eraser cost 12cents more than a pencil ,12pencils cost 24cents more than than 8erasers.Find the cost 10pencils.

一道简单的英语数学题,An eraser cost 12cents more than a pencil ,12pencils cost 24cents more than than 8erasers.Find the cost 10pencils.
设 铅笔的价格是 x 美分,那么橡皮擦的价格是 x-12 美分
12x-24=8(x +12) 解得 x=30
所以,10只笔的价格应该是 300美分.

设eraser =X pencil=Y
x+12=y,12y+24=8x,解得x=18,y=30
10y=300,
10pencils=300

eraser橡皮pencils铅笔
设橡皮价格X美分,铅笔价格Y美分
X=12+Y
8X+24=12Y
解得X=42 Y=30
故10支pencils铅笔300美分

10乘以(24÷12)=20

An eraser needs 42 cents . a pencil needs 30 cents.
so 10 pencils need 300cents.

it needs 20