9514 1404 393
Answer:
- 100 mL of 75% solution
- 150 mL of pure alcohol
Step-by-step explanation:
Let x represent the quantity (in mL) of pure alcohol needed for the mix. Then the amount of 75% needed is (250-x). The amount of alcohol in the mixture is ...
1.00x +0.75(250 -x) = 0.90(250)
0.25x +187.5 = 225 . . simplify
0.25x = 37.5 . . . . . . . . subtract 187.5
x = 150 . . . . . . . . . . . . . divide by 0.25
(250 -x) = 100 . . . . mL of 75% solution
You need 100 mL of the 75% solution and 150 mL of pure alcohol to obtain the desired mixture.
Answer: See attached picture
Step-by-step explanation:
Answer:
the angles always equal 180
Step-by-step explanation:
a) 20.9
The mean is calculated by adding up the scores and dividing the total by the number of scores, it is also called the average.
First, we can count and see there are 11 players (makes sense for a football team). Adding up the ages gives us 19 + 19 + 20 + 20 + 20 + 21 + 22 + 22 + 22 + 22 + 23 = 230. Divide by 11 and we get a mean of of about 20.9!
b) 30
To figure this out, we will set up an equation that looks like this:
And now we will solve:
[multiply both sides by 12] 230 + x = 264
[subtract 130 from both sides] x = 30
So the age of the new player should be 30!
Have a nice day!
I hope this is what you are looking for, but if not - comment! I will edit and update my answer accordingly. (ノ^∇^)
- Heather