the mean weight of 100 students in a certain class is 71kg the mean weight of boys is 65kg and that of girls is 75kg what is the number of boys and girls​

There are 60 girls and 40 boys in the class.

Step-by-step explanation:

Given that the mean weight of 100 students in a certain class is 71kg, while the mean weight of boys is 65kg and that of girls is 75kg, to determine what is the number of boys and girls the following calculation must be performed:

1 x 75 + 0 x 65 + 75

0.9 x 75 + 0.1 x 65 = 74

0.8 x 75 + 0.2 x 65 = 73

0.7 x 75 + 0.3 x 65 = 72

0.6 x 75 + 0.4 x 65 = 71

Thus, there are 60 girls and 40 boys in the class.

1) 2/5

2) zero=0/1

3) zero=0/2

4) -4/5

5) undefined=3/0

step-by-step explanation:

we have

using a graphing tool

see the attached figure

this is a quadratic equation (vertical parabola) open up

the vertex is a > vertex

the domain of the function is all real > interval (-∞,∞)

the range of the function is the > [-6.125,∞)

the function has two x->   and

the function is increasing over the > (0.25,∞)

the function is decreasing over the > (-∞,0.25)