Answer:
Explanation:
If quantities vary directly, then one is simply the other multiplied by a fixed number. All sets of two numbers in a direct variation are one number multiplied by a fixed number to get the second number.
Example:
1 gallon of gasoline costs $3.50
2 gallons of gasoline cost $7.00
3 gallons of gasoline cost $10.50
Is the price of gasoline a direct variation based on the number of gallons?
3.5/1 = 3.5
7/2 = 3.5
10.5/3 = 3.5
When you multiply 1 gal, 2 gal, and 3 gal by the constant number 3.5 $/gal, you get the price. Since the multiplication is always by the same number, it is a direct variation.