Answer:
C) 21 girls : 9 boys
Step-by-step explanation:
You just have to compare the ratio you're given to the answers and see if the ratios from the answers match up to the ratio you were given. The reason C is the answer is because if you divide by 3 in the ration, it is the same as the ratio you were given, 7:3
Answer:I think a is:78.3 since it would be the same and since 0 doesn't have a value.
I think b is: 139.5 because all you are doing is subtracting 287.1-147.6
If that's an addition sign, then b=-35.
If it's a division sign, then b=-150
Sorry I can't see which it is! Hope this helped though :)
Good luck!
Answer:
17000 batteries
Step-by-step explanation:
Three years and one month is equivalent to the mean minus one standard deviation.
Three years and seven months is equivalent to the mean plus one standard deviation.
For a normal distribution, we know that 68% of population is between mean ± 1 sd, then can be expected that 25000*68% = 17000 of batteries last between three years and one month and three years and seven months
let's say the bill without the tip is "x" amount, so that'd be the 100% of the bill, but we also know that 4.50 is the 18% of "x".
so if 4.50 is the 18% of "x", how much is "x"?
