There are 3 feet in 1 yard. 300 feet is equal to 100 yards.
2 pieces of rope at 16 yards = 32 yards
1 piece of rope at 12.5 yards = 12.5 yards
1 piece of rope at 123.25 feet, divided by 3 feet per yard = 41.1 yards (approx.)
100 - 32 - 12.5 - 41.1 = 14.4 yards
Now multiply by this number of yards by 3 to convert it to feet.
14.4 x 3 = 43.2 feet
The school club needs 43.2 feet of additional rope.