Answer: There are 11 gallons which will be used by him to paint the inside of his barn.
Step-by-step explanation:
Since we have given that
Total number of quarts he needed in all =107
Let the number of quarts he needed for the inside of his barn be x
Let the number of quarts he needed for the outside of his barn be x+19
According to question,
[tex]x+x+19=107\\\\2x+19=107\\\\2x=107-19\\\\2x=88\\\\x=\frac{88}{2}\\\\x=44[/tex]
As we know that
[tex]1\text{ gallon}=4\text{ quarts}\\\\so\\\\1\text{ quarts}=\frac{1}{4}\text{ galllon}\\\\44\text{ quarts}=\frac{44}{4}\text{ gallons}=11\text{ gallons}[/tex]
So, there are 11 gallons which will be used by him to paint the inside of his barn.