Answer:
so 39× . 27 =10.53
that would be an accurate estimate
I tried my best with 1, 2, and 3
<span> first, write the equation of the parabola in the required form: </span>
<span>(y - k) = a·(x - h)² </span>
<span>Here, (h, k) is given as (-1, -16). </span>
<span>So you have: </span>
<span>(y + 16) = a · (x + 1)² </span>
<span>Unfortunately, a is not given. However, you do know one additional point on the parabola: (0, -15): </span>
<span>-15 + 16 = a· (0 + 1)² </span>
<span>.·. a = 1 </span>
<span>.·. the equation of the parabola in vertex form is </span>
<span>y + 16 = (x + 1)² </span>
<span>The x-intercepts are the values of x that make y = 0. So, let y = 0: </span>
<span>0 + 16 = (x + 1)² </span>
<span>16 = (x + 1)² </span>
<span>We are trying to solve for x, so take the square root of both sides - but be CAREFUL! </span>
<span>± 4 = x + 1 ...... remember both the positive and negative roots of 16...... </span>
<span>Solving for x: </span>
<span>x = -1 + 4, x = -1 - 4 </span>
<span>x = 3, x = -5. </span>
<span>Or, if you prefer, (3, 0), (-5, 0). </span>
Step 1:
First, find the total number of students.
Let the total number of students = m
Step 2:
Find the total number of students using the percentage of 4 books.
48 students listed 4 books with a percentage of 16%

Hence, there are 300 students.
a)

72 students had 1 book.
b) What percentage more read 2 books than 4 books?
percentage that read 2 books = 36%
percentage that read 4 books = 16%
36 - 16 = 20%
There are 20% students that read 2 books than 4 books.