Question

a+ b+c=255
b:a= 2 rest 1
c:b = 3 rest 8

Answer 1

b=2a+1
c=3b+8=3(2a+1)+8
c=6a+11

a+2a+1+6a+11=255
9a=255-12
9a=243
a=27
b=2×27+1=55
c=6×27+11=173

Answer 2

a + b + c = 255

b : a = 2 rest 1 ⇒  b = 2 × a + 1

c : b = 3 rest 8 ⇒  c = 3 × b + 8 = 3 × ( 2 a + 1 ) + 8 = 6 a + 11

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a + b + c = 255

a + ( 2 a + 1 ) + ( 6 a + 11 ) = 255

9 a + 12 = 255

9 a = 255 - 12

9 a = 243

a = 243 : 9 ⇒   a = 27

b = 2 × 27 + 1   ⇒ b = 55

c = 3 × 55 + 8 ⇒ c = 173

Verific:

27 + 55 + 173 = 225