Can someone help me with this and explain please? No links

Her refund would be $5,681.20.

The problem says that Laura paid the estimate above, which is 28%.
0.28 x 134350 = 37618

However, she had some deductions.
134350 - 4000 - 12200 - 4090 = 114060

So, to find the tax on this amount, we multiply it again by 0.28.
0.28 x 114060 = 31936.8

The amount of the refund will be the difference.
37618 - 31936.8 = 5681.2