Martin has just as brothers as sisters. His sister Jana but has 2 times more brothers than sisters.

a) How many children are in this family?
b) How many boys and how many girls are in the family?

Correct answer:

a =  7
b =  4
c =  3

Step-by-step explanation:

a = b+c
b -1 = c
2(c - 1) = b

a = b+c
b -1 = c
2•(c - 1) = b

a-b-c = 0
b-c = 1
b-2c = -2

a = 7
b = 4
c = 3

Our linear equations calculator calculates it.

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