28min/2lawns = 14min per lawn. Then 14min * 5 lawns = 70min
T
adds 6
t-6
divides by 6
(t-6)/6
shawn
7+t
divide by 7
(7+t)/7
theyare equal
(t-6)/6=(7+t)/7
times 42 both sides
7(t-6)=6(t+7)
distribute
7t-42=6t+42
minus 6t both sides
t-42=42
add 42 both sides
t=84
28 is the correct answer.
Answer:
2x^3/x+5/x-5/ 3x-1
2x^3/ 3x-1
Step-by-step explanation:
we can cut plus and minus sign
<h2>
Answer with explanation:</h2>
The confidence interval for population mean is given by :-
(1)
, where
= sample mean
z* = critical value.
SE = standard error
and
,
= population standard deviation.
n= sample size.
As per given , we have


n= 15
It is known that ring diameter is normally distributed.
By z-table ,
The critical value for 95% confidence = z*= 1.96
A 99% two-sided confidence interval on the true mean piston diameter :
(using (1))

[Rounded to three decimal places]
∴ A 99% two-sided confidence interval on the true mean piston diameter = (74.020, 74.022)
By z-table ,
The critical value for 95% confidence = z*= 1.96
A 95% lower confidence bound on the true mean piston diameter:
(using (1))
[Rounded to three decimal places]
∴ A 95% lower confidence bound on the true mean piston diameter= 74.020