Question

324+3x{386+[48+2x(5xa-16x5)]}=1866

Answer 1

324 + 3 · {386 + [48 + 2 · (5 · a - 16 · 5)]} = 1866
324 + 3 · {386 + [48 + 2 · (5 · a - 80)]} = 1866
3 · {386 + [48 + 2 · (5 · a - 80)]} = 1866 - 324 = 1542
386 + [48 + 2 · (5 · a - 80)] = 1542 : 3 = 514
48 + 2 · (5 · a - 80) = 514 - 386 = 128
2 · (5 · a - 80) = 128 - 48 = 80 
5 · a - 80 = 80 : 2 
5 · a - 80 = 40
5 · a = 40 + 80 
5 · a = 120
a = 120 : 5 
a = 24

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