The output is the cube of the input.

Yes it is right because you are measuring by either the base to height or length times width

X=hours master worked
y=hours apprentice worked

62x+40y=492

if master worked 3hours more than apprntice
x=3+y

sub 3+y for x

62(3+y)+40y=492
expand
186+62y+49y=492
186+102y=492
minus 186 both sides
102y=306
divide both sides by 102
y=3

sub back
x=3+y
x=3+3
x=6

master electrician worked 6 hours
6*62=372

master electrician earned $372