Answer:
47.4167
D. The computed mean is close to the actual mean because the difference between the means is less than 5%
Step-by-step explanation:
Given the distribution :
Speed(m/hr) ___ midpoint(x) ___ F ___fx
42 - 45 _______ 43.5 ________21 __ 913.5
46 - 49 _______47.5 _________15 __712.5
50 - 53 _______ 51.5 _________6 __ 309
54 - 57 _______ 55.5 ________ 4 ___ 222
58 - 61 ________59.5 ________ 2 ___ 119
The midpoint, x= sum of lower and upper boundary divided by 2
For instance, (42 + 45) / 2 = 43.5
The computed mean, Σfx / Σf = 2276 / 48 = 47.4167
Actual mean = 47.3 miles
(47.4167 - 47.3) / 47.3 * 100% = 0.24%
16 is the answer when multiplied by each side
We can see that 2x - 8x + x = -5x
and -6y + 11y = 5y
and 9 - 14 = -5
so simplified, it is -5x + 5y - 5
Hope you could understand.
If you have any query, feel free to ask.
It's multiplied by 5, so the amplitude is 5.
The period is pi/2 since it's tan(2t)