Final answer:
Tom took $47.32 with him to the mall.
Step-by-step explanation:
To find out how much money Tom took with him to the mall, we need to add up his expenses and subtract that from the amount he had when he left the mall.
Tom bought 2 shirts for $23.12, so each shirt cost $23.12 / 2 = $11.56.
He also bought a hat for $6.25, and lunch for $6.17.
So, his total expenses at the mall were $11.56 + $11.56 + $6.25 + $6.17 = $35.54.
If he had $11.78 remaining when he left the mall, then he took $35.54 + $11.78 = $47.32 with him to the mall.