Two different age groups were surveyed about the amount of time they spent on social media.
Frequency
The results are shown on the two frequency
polygons below. The same time intervals were
used for both graphs.
a) How many 18-year old
students took part in
12-year old students
18-year old students
the survey? 320
80
801
70
70
60
60
b) How many more 18-year
50
50
old students than 12-year
30
old students spent
between 25 and 35 mins
20
20
on social media?
10
10
0
0
0 10 20 30 40 50 60 70 80 0 10 20 30 40 50 60 70 80
Time (mins)
Time (mins)
Frequency
840
30

1 x=22.52

2: 65/39=604+39x

65x-39x=604

26x=604

x=604/26

×=23.23

a triangular prism is a 3 dimensional shape composed of triangles and rectangles. it is made from two triangular bases and three rectangular sides.  

the speed is   miles per hour > is false

step-by-step explanation:

we know that  

a relationship between two variables, x, and y, represent a proportional variation if it can be expressed in the form or

in a proportional relationship the constant of proportionality k is equal to the slope m of the line and the line passes through the origin

the graph shown in the figure represent a direct variation

the slope of the line represent the speed

for the point

substitute the values of x and y

the linear equation is equal to

statements

case a) it takes hours to go miles

the statement is true

because

substitute

for

find the value of y in the linear equation

> is correct

case b) the speed is   miles per hour

the statement is false

because the speed is

case c) the unit rate for the trip is

the statement is true

because the speed is equal to the slope of the linear equation

case d) it took minutes to go the first miles

the statement is true

because

substitute

for

find the value of y in the linear equation

> is correct