Question

1. 37.8 x 14 = ______ x 14 - 2.9 x 14

Answer 1

Answer:

2

Step by step explanation:

Given: The average mass of all the students in the class was 35.1 kg. After 1 student left the class, whose mass is 32.3kg, the average mass of the remaining students became 36.3kg, how many students were there in the class room now?

Find out: how many students were there in the class room after one student left

Solution: Let the total number of remaining student be= n

Let the total number of remaining student be= nAnd the sum of mass of all the students be = x kg

So,

$\frac{x}{n + 1} = 35.1$

Make x the subject of formula

$--› \: x = 35.1(n + 1)$

And

$--› \: \frac{x - 32.3}{n} = 36.3$

$--›x - 32.3= 36.3n$

$--› \: 35.1(n + 1) - 32.3 = 36.3n$

$--› \: 35.1n + 35.1 - 32.3 = 36.3n$

$--› \: 2.8 = 1.2n$

divide both side by n

$n = \frac{2.8}{1.2}$

N = 2.333

so total number of students remaining is 2