Answer:
10 seconds
Step-by-step explanation:
Elliot finishes the race in 1/2 of 20 sec or 10 sec
Answer:
(x+y)(x-y-1)
Step-by-step explanation:
x²-y²-x-y= (x+y)(x-y)-(x+y)= (x+y)(x-y-1)
Answer:
Step-by-step explanation:
R=3 S=5 then it's 3x5 which is 15
3x2=6
Next do 15+6=21
Then do 21x3.14=65.94
Answer:

And we can use the normal standard distribution table or excel and with the complement ruler we got:

Step-by-step explanation:
We know the following info given:
represent the true mean
represent the population deviation
represent the sample size selected
Since the sample size is large enough (n>30) we can use the central limit theorem and the sample mean would have the following distribution:

And for this case we want to find this probability:

And we can use the z score formula given by:

And replacing we got:

And we can use the normal standard distribution table or excel and with the complement ruler we got:

Step 1: Flip the equation.
−
x
+
4
=
−
8
Step 2: Subtract 4 from both sides.
−
x
+
4
−
4
=
−
8
−
4
−
x
=
−
12
Step 3: Divide both sides by -1.
−
x
−
1
=
−
12
−
1
x
=
12
Answer:
x
=
12