Here is what your frequency/cumulative frequency table would look like. The cumulative frequency is where you add all the frequencies from before it to get a sum after each interval.
<u> Frequency </u> <u>Cumulative Frequency</u>
0-25 8 8
26-50 0 8
51-75 4 12
76-100 2 14
12/3=4
so m=4
6x4=24
6x1=6
24-6=18
Step 1: Find the slope:

Step 2: Set up your equation
using one of the points.
Using (5,6) we have
.
Using (6,10) we have 
Both of those equations would be correct.
These are exponents. To solve an exponent you need to multiply the base it self how many times its says in the power.
a²
a = base
<span>2 = power
</span>
7^5 = 7 × 7 × 7 × 7 × 7 = <span>16807
7^5 = </span><span>16807</span>