89 points! hurry within 2 minutes. jered's parents are going to repaint their house. they need to select two colors to complete the job. if they previously narrowed their decision down to six colors, how many combinations of two can they choose from?

The formula for combinations is n! / (r!(n-r)!)

where n is the total number of objects and r is the sample.

So you get 6! / (2!(6-2)!)

The ! means you multiply the number by all numbers below it

so 6! = 6 * 5 *4 * 3 *2 *1  = 720

2! = 2*1 = 2

6-2 = 4, 4! = 4 * 3 *2 *1 = 24

Now you have 720 / 2 * 24 =

720 / 48

Answer = 15 possible combinations.

step-by-step explanation:

12: 00 p.m. to 7: 00 p.m. is a total of 7 hours.

4: 00 p.m. to 7: 00 p.m. is a total of 3 hours.

this means that from 4: 00 p.m to 7: 00 p.m. this represents 3/7 of what was lost from 12: 00 p.m. to 7: 00 p.m.

after knowing this, after doing 11,600 - 6,800 = 4,800

4,800 represents 3/7 of what was lost for 7 hours.

we then divide 4,800 by 3 which gets 1,600.

because we know that 1,600 represents 1/7 of how much water was lost, we just have to multiply by 7, which gets 11,200.   after adding 11,200 to how much water was left at 7: 00 p.m. which was 6,800. 11,200 + 6,800 = 18,000

this means that the pool originally had 18,000 gallons in the pool.

you can also check your work by doing 18,000 - 4(1600), which becomes           1800 - 6400 which gets you 11,600.