21 times 31 plus 3 divided by 7 times 4 minus 390 plus 33 times 33 plus 33 divided by 90 divided by 8000

Actual is 1,351.7143315
estimate or rounded is 1,351.714

21*31+3/7*4-390+33*33+33/90/8008 = 1351.71433

I show an example in the picture below. If you know how to solve with Pythagorean theorem this problem should be fairly easy. All you have to do is make 2 triangles and solve for C. Once you solve for C for both triangles you should get 20 for one answer and 15 for the other answer. Then all you do is just add them together so your answer should be 35 feet.