Answer:
3 gallons of diesel weight = 22.2 pounds
The constant of variation = 7.4
The quantities vary directly
Explanation:
Given:
5 gallons of gas weights = 37 pounds
To find
a) the weight of 3 gallons of gas.
b) if the quantities vary directly or inversely.
c) the constant of variation.
Solution:
Applying unitary method to find weight of 3 gallons of gas.
If 5 gallons weight = 37 pounds
Then, 1 gallon will weight =
=7.4 pounds
Thus, 3 gallons will weight =
= 22.2 pounds
Listing out the data we have:
1 gallon = 7.4 pounds
3 gallons = 22.2 pounds
5 gallons = 37 pounds
From the data, we find out that as the number of gallons of gas increases the weight of gas also increases. This shows that these quantities are directly proportional to each other.
The unit rate of the quantities is called the constant of variation.
Unit rate: 7.4 pounds per gallon
Thus, the constant of variation = 7.4