Answer: $0.44
Explanation:
Since Marco has $1.31 in his coin bank and he spends 87c to buy a pen, the amount taht will be left with him after he buys the pen will be gotten by subtracting 87cents from $1.31.
Note that 100 cents = $1
Therefore, $1.31 will be = 100 × 1.31 = 131 cents.
Therefore, 131 cents - 87 cents = 44 cents or $0.44
He has $0.44 left