Question 560887
let b = no. of blue bikes
let y = no. of yellow
let g = no. of green
:
Write an equation for each statement:
:
"There are 18 bikes in a bike rack."
b + y + g = 18
:
" There are 4 more blue bikes than yellow bikes,"
b = y + 4
:
"and 2 less yellow bikes than green bikes."
y = g - 2
We want to get g in terms of y also
add 2 to both sides
g = y + 2
:
In the 1st equation: replace b with (y+4); replace g with (y+2)
b + y + g = 18
(y+4) + y + (y+2) = 18
Combine like terms
3y + 6 = 18
3y = 18 - 6
3y = 12
y = 12/3
y = 4 yellow bikes
then
b = y +4
b = 4 + 4
b = 8 blue bikes
and
g = y + 2
g = 4 + 2
g = 6 green bikes
:
Check this by seeing if they add up to 18
8 + 4 + 6 = 18