Question

Out of total 10 students the average weight of 9 students is 69kg.If the weight of 10th student is 9kg more then the average of 10 student.so what is the average weight of students.​

Answer 1

Answer:

The average weight of the students  is 70 kg

Step-by-step explanation:

Let the average weight of the 10 students be x

Given:

Average weight of the 9 students=69 kg

Sum of the weights of 9 students =69*9=621

As per given data,

weight of the 10th student=x+9

Therefore,

Sum of the weights of 10 students=621+x+9=630+x

Now,

Average weight of 10 students = x

$\implies\frac{630+x}{10}=x$

$\implies\,630+x=10x$

$\implies\,630=9x$

$\implies\,x=\frac{630}{9}$

$\implies\bf\;x=70$

$\therefore$The average weight of students is 70 kg