Answer:
Noah's expression is wrong because he used the wrong coefficients for the variables, and he used a subtraction sign instead of an addition sign.
The correct expression is 2m + 10c
Explanation:
Noah is incorrect because he used the wrong coefficients for both of the variables in the expression.
Since muffins are $2 each, and m is the number of muffins, the amount of money made from the muffins is 2m, not 10m.
Similarly, since cakes are $10 each, and c is the number of cakes, the amount of money made from the cakes is 10c, not 2c.
Noah is also incorrect because he used a subtraction sign instead of an addition sign. The amounts made from the muffins and cakes have to be added together.
Putting all of this together, the correct expression is 2m + 10c.