Answer:
Sheila have 6 bills
Step-by-step explanation:
Suppose Sheila has x '20' dollar bills, so the total cost of her bill = $20x
Suppose Tamsin has y '10' dollar bills, so the total cost of her bill = $10y
<h3>Equation 1</h3>
<em>Sheila has a total of $50 more than Tamsin</em>
<h2><em>10y + 50 = 20x</em></h2><h2 /><h3>
Equation 2</h3>
<em>Tamsin has 1 more bill than Sheila.</em>
<h2>y = x + 1 </h2><h2 />
<em>Now solve them by putting value of x in equation </em>
10( x + 1 ) + 50 = 20x
10x + 10 + 50 = 20x
60 = 20x - 10x
10x = 60
x = 60/10
x = 6
and
y = 7
<em> </em>