Simplify the expression and you get: 8.6
Hope this helps!
The inequality should read:

Subtract 2 from all the terms:

Divide all the terms by -5 to get x by itself (note that you flip the inequality signs as you divide by a negative):

The inequality is 2 ≤ x < 8.
A closed dot represents ≤, and an open dot represents <. Since x can represent all values between 2 and 8, you will shade in between 2 and 8 on the number line. x is greater than or equal to 2, so there will be a closed dot on 2. x is less than 8, so there will be an open dot on 8.
The answer is 'number line with a closed dot on 2 and an open dot on 8 and shading in between'.
To solve this problem we will start by calculating time needed for each of them to fill the pool.
We have formula:
Volume = rate * time
Or
time = volume / rate
Wilma:
time = 9900 / 900
time = 11h
Betty:
time = 9900 / 500
time = 19.8h
Now we substract these two numbers:
time_difference = 19.8 - 11 = 8.8h
Betty needs 8.8 hours more than Wilma to fill the pool.
12 red counters
7 more red counters than yellow counters
12 - 7 = 5 yellow counters
Dara has 5 yellow counters.