Caitlin has 27 $5 bills and 54 $10 bills.
Step-by-step explanation:
Given,
Worth of $5 and $10 bills = $675
Let,
Number of $5 bills = x
Number of $10 bills = y
According to given statement;
5x+10y=675 Eqn 1
She has twice as many $10 bills as $5 bills.
y=2x Eqn 2
Putting value of y from Eqn 2 in Eqn 1

Dividing both sides by 25

Putting x=27 in Eqn 2

Caitlin has 27 $5 bills and 54 $10 bills.
Keywords: linear equation, substitution method
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