The total amount of red paint did they use is 2.3 liters and this can be determined by forming the linear equation in one variable.
Given :
The following steps can be used in order to determine the amount of red paint did they use:
Step 1 - The linear equation can be formed in order to determine the amount of red paint did they use.
Step 2 - The linear equation that represents the total paint in both the jars is given below:
p + 0.6 + p - 0.4 = 2.4 + 2.4
Step 3 - Simplify the above equation in order to determine the value of 'p'.
2p + 0.2 = 4.8
2p = 4.6
p = 2.3 liters
So, the total amount of red paint did they use is 2.3 liters.
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https://brainly.com/question/2263981