15−42:2= 15-4^2:2= 15−42:2=
First, compute the power: 42=16 4^2 = 16 42=16.
Next, divide: 16÷2=8 16 \div 2 = 8 16÷2=8.
Finally, subtract: 15−8=7 15 - 8 = 7 15−8=7.
7 7 7