1st equation x - 7 < 14:
x < 14 + 7 (add 7 to both sides)
x < 21 (add 14 + 7 so it can equal 21)
2nd equation x + 13 > 21:
x > 21 - 13 (subtract 13 from both sides)
x > 8 (subtract 21 - 13 so it can equal 8)
The frequency of revision times is given by the product of the frequency
density value and the class width.
Correct response:
- The number of students are <u>72 students</u>
<h3>Methods of calculation using a histogram</h3>
The estimate of the number of students who revised for less than 45
minutes is given by the area, <em>A,</em> under the histogram to the left of the 45
minute mark as follows;
Frequency, f = Frequency density × Class width
Number of students = ∑f
Therefore;
A = 5 × 2 + 10 × 2.2 + 20 × 1.6 + 10 × 0.8 = 72
- The number of students that revised for less than 45 minutes = <u>72 </u>students
Learn more about histograms here:
brainly.com/question/17139138
Perpendicular lines will have negative reciprocal slopes
B. y = -4x+ 5 and y = 1/4x + 4
D. y = x + 4 and y = -x + 4
E. y = -3 and x = -3
You can start by doing 3×3 which is 9 than get the 9 and multiply it by 11 which would be 99