Question

Nicole is buying dog nuts for the bus ride to cheer competition. Plain glazed donuts are $4 per box and chocolate cake donuts cost $5 per box. She spends a total of $91 for 20 boxes. How many boxes of each kind of donut did she buy?

Answer 1

Answer: We can start solving this problem by using a system of equations. Let x be the number of plain glazed donuts Nicole buys, and y be the number of chocolate cake donuts she buys. We know that:

x + y = 20 (The total number of boxes of donuts she buys is 20)

4x + 5y = 91 (The total amount of money she spends is $91)

We can use the first equation to solve for one variable in terms of the other. For example, we can substitute x = 20 - y into the second equation:

4(20 - y) + 5y = 91

80 - 4y + 5y = 91

-4y + 5y = 91 - 80

y = 11

So Nicole bought 11 boxes of chocolate cake donuts. We can substitute that back into the first equation to find the number of plain glazed donuts she bought:

x + 11 = 20

x = 9

So Nicole bought 9 boxes of plain glazed donuts.

We can check our answer by substituting our values of x and y back into the original equations:

x + y = 9 + 11 = 20 (This is the total number of boxes of donuts she bought, which is 20)

4x + 5y = 4(9) + 5(11) = 91 (This is the total amount of money she spent, which is $91)

Both equations are true, so our solution is correct.

Explanation: