Question

There are 45 students in a class.The no. of boys is 5 more than girls. The average weight of boys is 5 more than the average weight of girls. The total weight of boys is 100 more than girls. Calculate the average weight of the class?

Answer 1

Answer:

42.22

Step-by-step explanation:

let X be no.of girls

given X+5 = no.of boys

so X+X+5=45

X= 20 girls

X+5= 25 boys

given avg wgt of boys is 5 more than girls boys(b) and gilrs (g) : b/25 +5 = g/20 4b-5g=-500..... equation 1

given b-g = 100 multiply this with 4

4b-4g= 400 ...... equation 2

by subtracting 1 and 2

-g= -900 g= 900

substitute g in b-g = 100 we get b= 1000

total wgt is 1900 and total strength is 45

avg = 1900/45=42.22