Answer: $9.90.
Explanation:
The total amount Sally spent is the sum of the cost of the soft drink and the hamburger and fries, which is $1.50 + $3.60 = $5.10.
To calculate how much money she has left from her allowance of $15, subtract the amount she spent from her total allowance.
$15 - $5.10 = $9.90
So, the answer is $9.90.