39.) His first score was 69. His second score was 71. That adds up to 140. If his mean is 72, what was his score on his 3rd try?
Okay so, 69 + 71 is 140. The total of his score will be 72 once divided by 3.
So if you make an equation to represent this it will be x/3 = 72
To figure this out you have to cancel out the 3 on the left side. You do this by multiplying by 3 on BOTH SIDES. Which gives you x/3*3 = 72*3
When you simplify it, it will give you x = 216. But this is ONLY GIVING YOU THE TOTAL OF THE THREE SCORES. Now you have to subtract 140 from 216 which gives you 76.
39.) D. 39
40.) I don't know how to solve this. I am sorry that I didn't find the answer.
41.) I don't know how to solve this. I am so sorry
42.) I don't know this one either. I am so so so so sorry
