Question

The average weight of a group of 10 people is 80 kg. if one is replaced by another person of weight 50 kg, the average weight of the group increases by 1 kg. what is the weight of the person removed from the group?

Answer 1

hope it helps...........

Answer 2

Answer:

40 kg

Step-by-step explanation:

The average weight of a group of 10 people is 80 kg.

$Average = \frac{\text{Sum of weights of 10 people}}{10}$

$80 = \frac{\text{Sum of weights of 10 people}}{10}$

$80 \times 10  = \text{Sum of weights of 10 people}$

$800  = \text{Sum of weights of 10 people}$

Now we are given that  one is replaced by another person of weight 50 kg

Let the weight of the  person removed from the group be x

So, New sum of weights = Sum of weights of 10 people -x +50

New sum of weights = 800 -x +50 = 850-x

We are also given that the average weight of the group increases by 1 kg.

So, $80+1= \frac{850-x}{10}$

$81= \frac{850-x}{10}$

$81 \times 10= 850-x$

$810= 850-x$

$x=40$

Hence the weight of the person removed from the group is 40kg