设pins数量为x,ribbons数量为y
那要筹集60美元的话
就是4x+2y=60
you dont know how many pins and ribbons there are,
so set the numbers of pins as"x" and the number of ribbons as"碰前闷笑弯悔扒y",
pins cost $4each (so total pins cost: 4x)
ribbons cost $2 each(so total ribbons cost: 2y)
together they add up to $60,
so put the numbers into the equation:
total pins cost+total ribbons cost=total cost
4x+2y=60
懂了吗?
maybe you should use GAC,
like this:
if both has 1 each,so the total would be,$6(4+2=6)
if each has 2,the total would be 6*2=12,
60devided by 6=10