Answer:
8πcm² = 8pi cm²
Step-by-step explanation
The formula for area of a sector = ½r²θ
Where r = radius = 6cm
θ = central angle = 4pi/9 in radians = 4π/9
Area of the sector = 1/2 × 6² × 4π/9
Area of the sector = (144π/18)cm²
Area of the sector = 8πcm²
Therefore, Area of the sector =
8πcm² = 8pi cm²
Answer:
81, 000
Step-by-step explanation:
86 = 90
904 = 900
90 x 900 = 81, 000
T=tickets sold
alrighty, so we need 400 and we have 75
what we need must be greater than or equal to the cost
cost=400
what we need=what we have+what we will earn
what we have=75
what we will earn=cost per ticket times number of tickets=4 times t=4t
so
75+4t≥400 would be a possible inequality
Answer:
The margin of error for the true mean number of hours a teenager spends on their phone is of 0.4 hours a day.
Step-by-step explanation:
We have the standard deviation of the saple, so we use the t-distribution to solve this question.
The first step to solve this problem is finding how many degrees of freedom, we have. This is the sample size subtracted by 1. So
df = 50 - 1 = 49
95% confidence interval
Now, we have to find a value of T, which is found looking at the t table, with 49 degrees of freedom(y-axis) and a confidence level of . So we have T = 2
The margin of error is:
In which s is the standard deviation of the sample and n is the size of the sample.
The margin of error for the true mean number of hours a teenager spends on their phone is of 0.4 hours a day.