Arandom sample of 200 dancers were asked if they practice dancing 20 h or more per week. the results are shown in the table.

Correct; incorrect; incorrect

Step-by-step explanation:

In the table, we see that there were 113 ballet dancers.  All of them practice 20 hours or more each week.  This means the first statement, "The ballet dancers practice 20 h or more per week," is correct.

We see that there are 87 jazz dancers.  None of them practice 20 hours or more each week.  This means the second statement, "The jazz dancers practice 20 h or more per week," is incorrect.

The last statement is also incorrect; this is because since ballet dancers all practice 20 hours or more, and none of the jazz dancers practice 20 hours or more, the type of dancing seems to directly affect the number of hours practiced per week.

answer:

it is general formula that is used to write value to its excet position

a11 a12 a13

a21 a22 a23

it is the example of order 2 by 3 matrix in this

a11 means value occur in 1 st row 1st column

a12 means value occurs in 1st row 2nd column

a13 means value occur in 1st row and 3rd column

a21 means value occurs in 2nd row and 1st column

a22 means value occurs in 2nd row and in 2nd column

a23 means value occurs in 2nd row and in 3rd column

8

step-by-step explanation: