Respuesta :
The total number of fives bills is 12 and the total number of tens bills is 18 and this can be determined by forming the linear equations.
Given :
Sarah has 30 bills in her wallet worth $240, all fives and tens.
The following steps can be used in order to determine the total number of fives bill and tens bills:
Step 1 - Let 'x' be the total bills of fives and 'y' be the total bills of tens.
Step 2 - The linear equation that represents the total number of bill is given by:
x + y = 30
x = 30 - y --- (1)
Step 3 - Now, the linear equation that represents the total amount of the bill is given by:
5x + 10y = 240 ---- (2)
Step 4 - Substitute the value of 'x' in equation (2).
5(30 - y) + 10y = 240
150 - 5y + 10y = 240
5y = 90
y = 18
Step 5 - Substitute the value of 'y' in equation (1).
x = 30 - 18
x = 12
So, the total number of fives bills is 12 and the total number of tens bills is 18.
For more information, refer to the link given below:
https://brainly.com/question/21835898