# The mean weight of a b and c is 50 kg is the mean weight of a and b is 40 kg and that of b and c is 45 find the weight of b

1
by zeb1

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by zeb1

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a + b + c / 3 = 50

a + b + c = 150 -- Eq.1

a + b / 2 = 40

a + b = 80 -- Eq.2

b + c / 2 = 45

b + c = 90 -- Eq.3

Eq.1 - Eq.2

a + b + c - a - b = 150 - 80

c = 70

Eq.1 - Eq.3

a + b + c - b - c = 150 - 90

a = 60

Putting these values in Eq.1

a + b + c = 150

60 + b + 70 = 150

130 + b = 150

b = 150 - 130

b = 20 kg