Question 178134
let x, y and z be the number of hard drive CD roms, and floppy drive sold, respectively
:
x+y+z=300.......eq 1
x=6y............eq 2
z=x/2..........eq 3
:
re write eq 2 to y=x/6. Now take that value of y which is x/6 and z's value from eq 3 which is x/2 and plug them into eq 1
:
x+(x/6)+(x/2)=300
:
6x+x+3x=1800........mulitiplied each term by 6 to get rid of fractions
:
10x=1800
:
{{{highlight(x=180)}}} hard drives sold
:
{{{highlight(y=x/6=180/6=30)}}}cd roms sold
:
{{{highlight(z=x/2=180/2=90)}}}floppies sold