Stan's heart rate, in beats per minute, was measured 20 times at random. The results are 82, 84, 98, 112, 97, 93, 91, 87, 112, 8
Licemer1 [7]
Answer:
(80.4942, 94.9052)
Step-by-step explanation:
The sample mean is x = 87.7.
The sample standard deviation is s = 11.26.
At 99% confidence and 19 degrees of freedom, the critical value is t = 2.861.
The confidence interval is:
x ± t (s/√n)
87.7 ± 2.861 (11.26 / √20)
87.7 ± 7.2053
(80.4947, 94.9053)
Answer:
32 muffins
Step-by-step explanation:
one cup of milk will make 32 muffins
you can set up a proportion of milk/muffins = milk/muffins
let 'x' = number of muffins made from one cup of milk
5/8 ÷ 20 = 1 ÷ x
cross-multiply to get 5x = 20(8)
5x = 160
x = 32
Answer:
F and C
Step-by-step explanation:
Answer:
Equation: x + (x+ 1) = 67
Step-by-step explanation:
We want to find two consecutive integers.
Let them be labeled as x and x + 1
We want x + (x + 1) = 67
x is the smaller number
x + 1 is the largest
We can solve for x.
x + (x + 1) = 2x + 1 = 67
2x = 66
x = 33
The largest integer is 34
11. 5x^2-30=0
+30 to both sides
5x^2=30
÷5 both sides
x^2=6
square root both sides
x= +square root 6 ,- square root 6
12. 4x^2+10=26
-10 both sides
4x^2=16
÷4 both sides
x^2=4
square root both sides
x=+2,-2
13. a=72yrd^2
l=2w
w=?
a=l×w
72=2w×w
72=2w^2
÷2 both sides
36=w^2
square root both sides
w=+6,-6
a measurement can't be - so w=6
Plug into l=2w
l=2×6
l=12
w=6