If a person whose average weight is $40 \mathrm{~kg}$ is replaced from a group of 30 persons and a new person comes, then the average weight is increased by $1 \mathrm{~kg}$. Find the weight of new person.
in Mathematics
8 views
1 Vote
1 Vote
If a person whose average weight is $40 \mathrm{~kg}$ is replaced from a group of 30 persons and a new person comes, then the average weight is increased by $1 \mathrm{~kg}$. Find the weight of new person.
in Mathematics
by
7.2k Points

1 Answer

1 Vote
1 Vote
 
Best Answer

Solution-

: Let the average wt. $=x$

$\therefore$ Total weight of 30 persons $=30 x$

The weight of new person $=y$

$$

\begin{array}{l}

\therefore 30 x-40+y=30(x+1) \\

\Rightarrow 30 x-40+y=30 x+30

\end{array}

$$

$\therefore y= 70 kg$


 Trick :

Required weight $=40+30 \times 1$

$=70 \mathrm{~kg}$; Ans.

by
7.2k Points

Related Questions

Categories

2.1k Questions

1.8k Answers

0 Comments

17 Users