Step-by-step explanation:
this is quite easy, when you use just common sense and identify the right numbers and variable names.
they is nothing special needed, you don't even need to create the equations yourself.
$4.99 per pound. buys b pounds and pays $14.95.
14.95 = 4.99 × b
$4.99 per pound. buys b pounds and pays c.
this is exactly the same as before, just that this time the total amount is not given as a constant but as a variable.
c = 4.99 × b
d dollars per pound. buys b pounds and pays t.
the same as the 2 cases before, just now everything is a variable. no more constants, but otherwise the completely same structure and method.
t = d × b
earned $275, which is $45 more than Noah ("n").
$275 = n + $45
earned m dollars, which is $45 more than Noah ("n").
m = n + $45
earned m dollars, which is y dollars more than Noah (we are asked that Noah's earnings are now called "v").
here your teacher made a mistake.
sure, the only remaining answer is
v = m + y
but it is not correct. given the names of the prime and associated variables the correct answer would be
m = v + y or v = m - y