Answer:
200 muffins
Explanation:
The selling price of each muffin = $2
The cost price of each muffin = $1.40
The price of electricity = $120
If the number of muffins that Jenny sells in a day is x, then, Jenny's total cost in a day is:
120 + (1.4 * x) = 120 + 1.4x
and the total sales earnings in a day for x muffins will be:
2 * x = 2x
To break even, the total costs in a day must equal to the total earnings. That is;
![2x = 120 + 1.4x](https://img.qammunity.org/2021/formulas/mathematics/high-school/hl6n55961sfqbjyb4idw5izmn5hktu0ht3.png)
Solving this:
![2x - 1.4x = 120\\\\\\0.6x = 120\\\\\\x = 120/0.6\\\\\\x = 200](https://img.qammunity.org/2021/formulas/mathematics/high-school/bs1niakt0tk9dmbjbulu0vx2ng1m3g5jvn.png)
She must sell 200 muffins in a day to break even.