Answer: in 95% of races, his finishing time will be between 62 and 64 seconds.
Step-by-step explanation:
The empirical rule states that for a normal distribution, nearly all of the data will fall within three standard deviations of the mean . The empirical rule is further illustrated below
68% of data falls within the first standard deviation from the mean.
95% fall within two standard deviations.
99.7% fall within three standard deviations.
From the information given, the mean is 63 seconds and the standard deviation is 5 seconds.
2 standard deviations = 2 × 0.5 = 1
63 - 1 = 62 seconds
63 + 1 = 64 seconds
Therefore, in 95% of races, his finishing time will be between 62 and 64 seconds.
It is given in the question that
Ann, Chang, and Kareem sent a total of 89 text messages over their cell phones during the weekend. Ann sent 9 fewer messages than Chang. Kareem sent 3 times as many messages as Ann.
Let number of messages Chang sent be x. And Ann sent 9 fewer than Chang, so Ann sent (x-9) messages. And Kareem sent 3 times as many messages as Ann, so Kareem sent 3(x-9) messages.
And the total messages are 89. That is
Combining like terms
So Chang sent 25 messages, Ann sent
And Kareem sent
A y-intercept is the value at which x = 0.
(4,0) is not a y-intercept because x = 4.
(-1, 1) is not a y-intercept because x = -1.
(0,0) is a y-intercept because x = 0.
(0, -7) is a y-intercept because x = 0.
(-2, 2) is not a y-intercept because x = -2.
(0, -0.25 is a y-intercept because x = 0.
26 divided by 10.92 equals 2.380952
Answer:
cost of producing the 501st item = $9.92
Step-by-step explanation:
The function representing the cost is given by;
C(x) = 10000 + 90x - 0.08x²
To get the cost of producing the 501st item, we have to first find the cost of producing 500 items and then do the same for 501 items then subtract the values gotten.
Thus;
C(500) = 10000 + 90(500) - 0.08(500)²
C(500) = 10000 + 45000 - 20000
C(500) = $35000
Similarly;
C(501) = 10000 + 90(501) - 0.08(501)²
C(501) = 10000 + 45090 - 20080.08
C(501) = $35009.92
cost of producing the 501st item = C(501) - C(500) = 35009.92 - 35000 = $9.92
