Please help! offering 15 points and a thanks with brainiest

Step-by-step explanation:

At least 6 hours means that the people took at least 6 hours and at most any number that is greater than 6. Here the greatest no. is 10.

So, the range for this will be 6-10

No. of People who sleep for 6-8 hours = 9

No. of People who sleep for 8-10 hours = 3

No. of People who sleep for 6-10 hours = 9+3

=> 12 people

or

step-by-step explanation:

we need to solve for 'x' the following equation:  

we have that:

⇒

⇒ ⇒

factorizing, we get that:

  ⇒

then, the solutions are: or

nothing extraneous has been found!