The scattered plot shows there is a close correlation between the variables. A line of best fit will go through the 'center' of the points. Since we are not required to find an exact line, we'll draw it in red color as shown below

To know the equation of that line, we must take two clear points of it from the graph. We'll pick (28,4) and (4,25)

The equation of a line, given two points (a,b) and (c,d) is

$\displaystyle y-b=\frac{d-b}{c-a}(x-a)$

Using the selected points

$\displaystyle y-4=\frac{25-4}{4-28}(x-28)$

Simplifying and computing results, the equation is

$\displaystyle y=-\frac{7}{8}x+\frac{57}{2}$

Using that equation, we can predict how many hours the students will spend doing homework if they spend 15 hours watching TV

$\displaystyle y=-\frac{7}{8}(15)+\frac{57}{2}$ =15.4 hours

So the student is expected to spend 15.4 hours doing homework

7 0

3 years ago

What is 24 percent of 99

yan [13]

Answer:

23.76%

Step-by-step explanation:

6 0

2 years ago

Multiply the sum of -13/8 and 5/12 by their difference.

REY [17]

Answer:

1421/576

Step-by-step explanation:

Sum = - 13/8 + 5/12 = - 39/24 + 10/24 = - 29/24

Difference = - 13/8 - 5/12 = - 39/24 - 10/24 = - 49/24

Sum * Difference = (-29/24)*(-49/24) = 1421/576

6 0

1 year ago

Toby buys packs of 12 racing cars for R49,99 and sells each racing car for R10 at school

Ratling [72]

Answer:

1.1 R5.83

1.2 R70.01

1.3 58.34%

Step-by-step explanation:

Given that he buys a pack of 12 racing cars for R49,99 then the unit cost for a car which is the total cost divided by the number of cars in a pack

= R49,99/12

= R4.17

If each car is sold for R10 then the profit made on each car which is the difference between the cost and the selling price

= R10 - R4.17

= R5.83

The profit margin on one pack of 12 racing cars

Profit margin is the ratio of the profit to the total selling price

The total profit (profit on one pack of 12 racing cars)

= R5.83 * 12

=R70.01

Total selling price = R10 * 12

=R120

Margin = R70.01 / R120

= 58.34%

4 0

2 years ago