Question

1) [930:3+(a+164):2+7]:5=100
2) 200-3×[(b×4:8+4):6+31]=80

Answer 1

1) [930:3+(a+164):2+7]:5=100
930:3+(a+164):2+7 = 100×5
310+(a+164):2+7 = 500
(a+164):2 = 500-310-7
(a+164):2 = 183
a+164 = 183×2
a+164 = 366
a = 366-164
a = 202

2) 200-3×[(b×4:8+4):6+31] = 80
3×[(b×4:8+4):6+31] = 200-80
3×[(b×4:8+4):6+31] = 120
(b×4:8+4):6+31 = 120:3
(b×4:8+4):6+31 = 40
(b×4:8+4):6 = 40-31
(b×4:8+4):6 = 9
b×4:8+4 = 9×6
b×4:8+4 = 54
b×4:8 = 54-4
b×4:8 = 50
b×4 = 50×8
b×4 = 400
b = 400:4
b = 100