Sagot :
Over the past year they sold 640 cars. Assuming Mike sells 3 times as many as Bill:
x --> cars sold (by Mike)
y --> cars sold (by Bill)
x + y = 640
x = 3y
3y + y = 640
4y = 640 |:4
y = 160
x = 3y = 3 * 160 = 480
Mike sold 480 cars and Bill sold 160 cars.
x --> cars sold (by Mike)
y --> cars sold (by Bill)
x + y = 640
x = 3y
3y + y = 640
4y = 640 |:4
y = 160
x = 3y = 3 * 160 = 480
Mike sold 480 cars and Bill sold 160 cars.
M+B=640
M=3B
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Therefore:
3B+B=640
4B=640
B=640/4=160
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M+160=640
M=640-160=480
Therefore, Mike had sold 480 cars.
M=3B
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Therefore:
3B+B=640
4B=640
B=640/4=160
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M+160=640
M=640-160=480
Therefore, Mike had sold 480 cars.