maths

a)Let Alan has the shop sold x records,
Anita has the shop sold y records
x+y=129----1)
110x+95y=12615----2)
From 1)
y=129-x----3)
sub. 3) into 2)
110x+95(129-x)=12615
110x+12255-95x=12615
110x-95x=12615-12255
15x=360
x=24
∴Alan has the shop sold 24 records.
b)129-24
=125
∴Anita has the shop sold 125 records.

2006-10-21 19:06:12 補充：
b)129-24=105∴Anita has the shop sold 105 records.

A SHOP HAS SOLD 129 records by Alan and Anita with a total sales of $12615 . Each record by Alan and each record by Anita are sold at $110 and $95 respectively . How many record
設Alan sold x records，Anita sold 129 - x records
110x + 95(129 – x) = 12615
110x – 12255 – 95x = 12615
15x = 360
x = 24
a)by Alan has the shop sold
24 records
b)by Anita has the shop sold
129 – 24
= 105 records