Question

36. 300 + 8 x 9 + 2 x [250-3x (28: b +66)] = 452 20​

Answer 1

300+8×9+2×[250-3×(28:b+66)]=45 220

300+72+2×[250-3×(28:b+66)]=45 220

72+2×[250-3×(28:b+66)]=45 220-300

72+2×[250-3×(28:b+66)]=44 920

2×[250-3×(28:b+66)]=44 920-72

2×[250-3×(28:b+66)]=44 848

250-3×(28:b+66)=44 848:2

250-3×(28:b+66)=22 424

3×(28:b+66)=22 424+250

3×(28:b+66)=22 674

28:b+66=22 674 :3

28:b+66=7 558

28:b=7 558-66

28:b=7 492

b=7492×28

b=209 776