Answer :
Let's say Tom has T silver dollars, and Jimi has J silver dollars.
If tom has 7 more dollars than Jimi, then we can express it as follows:
[tex]T=J+7[/tex]The total amount they both have is 77, then, it can be expressed as follows:
[tex]T+J=71[/tex]Now we have a system of two equations and two unknowns.
An easy way to solve this is replacing the first equation in the second:
[tex]J+7+J=71[/tex]Then, operating:
[tex]2J+7=71[/tex]Now, solving for J:
[tex]\begin{gathered} 2J=71-7 \\ 2J=64 \\ J=\frac{64}{2} \\ J=32 \end{gathered}[/tex]Now we have found how many silver dollars Jimi has. We can now use again the first equation we stated, replacing 32 where we have J:
[tex]\begin{gathered} T=J+7 \\ T=32+7 \\ T=39 \end{gathered}[/tex]Then, Tom has 39 silver dollars.
We can prove this because 39 is 7 more than 32, and 39 + 32 = 71