College

The mean weight of three people in a lift was 68 kg. If two of them weighed 58 kg each, how much did the third person weigh?

A. 78 kg
B. 83 kg
C. 88 kg
D. 93 kg
E. I don't know

Answer :

We are given that the mean weight of the three people is [tex]$68\text{ kg}$[/tex]. This means that the total weight of the three people is

[tex]$$
\text{Total weight} = 68 \times 3 = 204\text{ kg}.
$$[/tex]

Two of the people weigh [tex]$58\text{ kg}$[/tex] each, so their total weight is

[tex]$$
58 + 58 = 116\text{ kg}.
$$[/tex]

To find the weight of the third person, subtract the total weight of the two people from the overall total weight:

[tex]$$
\text{Third person's weight} = 204 - 116 = 88\text{ kg}.
$$[/tex]

Thus, the third person weighs [tex]$88\text{ kg}$[/tex].