SOLUTION: a van travels 150 miles on 6 gallons of gas. write and solve a proportion to determine the number of gallons needed to travel 500 miles

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Question 640285: a van travels 150 miles on 6 gallons of gas. write and solve a proportion to determine the number of gallons needed to travel 500 miles
Found 2 solutions by solver91311, josh_jordan:
Answer by solver91311(24713) About Me  (Show Source):
You can put this solution on YOUR website!




Cross-multiply and solve for

John

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Answer by josh_jordan(263) About Me  (Show Source):
You can put this solution on YOUR website!
We know that a van goes 150 miles per 6 gallons. In other words:
150+miles%2F6+gallons+of+gas
So, our proportion will look like this:
150+miles%2F6+gallons+of+gas+=+500+miles%2Fx+gallons+of+gas
Let's take out the words from our equation:
150%2F6+=+500%2Fx
When working with proportions (fractions) involving a variable, in this case x, we can multiply the numerator on the left side by the denominator on the right, and multiply the denominator on the left side by the numerator on the right:
150%2Ax+=+6%2A500, which gives us
150x+=+3000
We need to get x by itself on the left side of our equation, so we need to do the opposite of what's being done to x on the left side. X is being multiplied by 150, so to get x by itself, we need to divide both sides by 150, since division is the opposite of multiplication:
%28150x%29%2F150+=+3000%2F150, which equals
x+=+20
Therefore, 500 miles will use 20 gallons of gas