Edward earned $ 270 in interest
How/Solution:
Multiply $2,250 by 4% (0.04)
[ $2,250 x 0.04 = 90]
and it equal to 90, then multiply it again by 3 [ 90 x 3 = 270 ]
His new account balance is $ 2,520
Solution:
Add $2250 by $270
[ $2,250 + $270 = $ 2,520 ]