Answer:
74.72
Step-by-step explanation:
Given
mean
Standard deviation 
For Top 25%

and Z value for 75 % is 0.6744
Thus score which separates the Top 25% of students is


Answer:
No,
12.8 = 12.800
Obviously, 12.800 <u>< </u>12.815.

Answer:x= 5
Step-by-step explanation:
5x-12=63
>5x=63+12=75
>x=75÷5
>x=15
I'm going to assume you mean:
13 * (3/4) + x = 7 * (1/4)
Let's go ahead and simplify the right side.
7 * (1/4) = 1.75
So now we have:
13 * (3/4) + x = 1.75
Now let's take care of the right side. Multiplication before addition.
13 * (3/4) = 9.75
9.75 + x = 1.75
To isolate x, we subtract 9.75 from both sides.
9.75 - 9.75 + x = 1.75 - 9.75
x = -8
Hopefully I spaced this well. \('-')/
If x is how long your friend swims and y is how long you swim, the answer would be x + 15 = y