Answer:
141
Step-by-step explanation:
First, we choose two variables to represent the two unknown numbers, the number of hamburgers and the number of cheeseburgers.
Let x = number of hamburgers.
Let y = number of cheeseburgers.
Now we use the given information to write two equations using the variables we defined above.
"If a hamburger shop sold a combined total of 423 hamburgers and cheeseburgers"
x + y = 423
"the number of cheeseburgers sold was two
times the number of hamburgers sold"
y = 2x
We have a system of two equations.
x + y = 423
y = 2x
Since the second equation is already solved for y, we can easily use the substitution method. We substitute what y equals to (2x) for y in the first equation.
x + y = 423
x + 2x = 423
3x = 423
x = 141
Since we let x = number of hamburgers, we have the answer.
Answer: 141
