Question

1 The mark obtained by a student are 35 ,45 and 70 find the average mark


2) Average of 3 number is 12 is average of 1st numbers is also 12 find the third number

3)The average of 4 number is 496 if two of them are 58 and 64 find the average of renaming 2 numbers ​

Answer 1

Answer:

$2$

Step-by-step explanation:

Let the number of the passed candidates=x.

Then the number of the failed candidates=120-x.

Now the total of the marks obtained by 120 candidates=120×35=4200.

The total of the marks obtained by passed candidates=39×x=39x. and

the total of the marks obtained by failed candidates=(120−x)×15=4200.

Then the total=39x+(120−x)×15=4200

⟹24x=4200−1800

⟹x=100

So the number of passed candidates=100.

Ans-