$678.74 because you need $989.99 but you only have $311.25 so you need to subtract what you have and what you need( $989.999 $311.25 ) and you would get $678.74 now to check you have to add what you have and what you need($678.74 $311.25) and get $989.99
Step-by-step explanation: Sadly the school will not have enough money to update the school. The amount of money they made was,$ 2,367.5 dollars. They would need $2367.5 more to update the school.