Question 765853
Two parts, m and n.  

{{{m+n=42}}}


{{{5n=4m+48}}}, "five times the second part exceeds four time the first part by 48."
Five times the second part is 5n.
Four times the first part is 4m.
Exceeding 4m by 48 is 4m+48.


The choice is yours how to solve the two equations for m and n.  Maybe try m=42-n and substitute; {{{5n=4(42-n)+48}}} and simplify to solve first for n...
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{{{5n=168-4n+48}}}
{{{9n=168+48=216}}}
{{{highlight(n=24)}}}
therefore {{{highlight(m=18)}}}