Answer :
Answer:
Let F = The number of $5 bills and T = the number of $10 bills. She has 15 bills total, so:
F+T = 15
T = 15-F
She has $120 total:
$120 = ($5)*F + ($10)*T
$120 = $5*F + ($10)*(15-F) [Substitute 15-F in place of T]
120 = 5F + 150 - 10F
-30 = -5F
6 = F
Check:
T= 15-F = 15=6 = 9
$120 = ($5)*6 + ($10)*9
$120 = $30 + $90
$120 = $120
Elizabeth had 4 of $10 bills, 9 of $5 bills and 16 of $1 bill.
Equation
Let x represent the number of $10 bill, y represent the number of $5 bill and z represent the number of $1 bill. Hence:
10x + 5y + z = 101 (1)
Also:
y = x + 5 (2)
And:
z = 4x (3)
From equation 1, 2 and 3:
x = 4, y = 9, z = 16
Elizabeth had 4 of $10 bills, 9 of $5 bills and 16 of $1 bill.
Find out more on equation on: https://brainly.com/question/2972832