Answer:
56.3 kilometers per hour
Step-by-step explanation:
We know D = RT
where
D is distance
R is rate (speed)
T is time
Let's Bill's rate be "x". Thus using equation we can write:
D = xt
We know Eugene travelled 21.1 faster than Bill, so Eugene's rate is 21.1 + x. So we can write:
D = (21.1 + x)t
D = 21.1t + xt
Now, putting t = 1 in both since after 1 hour given, we have:
D = x(1)
D = x
and
D = 21.1(1) + x(1)
D = 21.1 + x
We know the sum of both the distance is 133.7, so we can write:
x + 21.1 + x = 133.7
Solving for x:
2x = 133.7 - 21.1
2x = 112.6
x = 112.6 / 2
x = 56.3 km/hr
This is Bill's rate: 56.3 kilometers per hour
So average is of the first 6 tests is 82 well that means
(test1 + test2+ test3+ test4 + test5+test6)/6 = 82
so now let do some cross multiplliying
test1 + test2 + test3 + test 4 + test5 +test6 = 82*6
test1 + test2 + test3 + test 4 + test5 +test6 = 492
now lets see if we can find that 7th test score
(test1 + test2 + test3 + test4 + test5 +test6 + test7)/7 = 80.5
So look we found test1 + test2 + test3 + test4 + test5 +test6 to be 492 so lets substitute.
(492 + test7 )/7 = 80.5
test7 = (80.5*7)-492 = 71.5
Answer:
s=10
Step-by-step explanation:
Basically, the range rule-of-thumb is that the range is generally about four times the standard deviation.
<u>First, we find the range:</u>
Range=Maximum-Minimum
Range=100-60
Range=40
<u>Next, divide the range by 4 to get the standard deviation</u>
Range=4(Standard Deviation)
40=4(Standard Deviation)
10=Standard Deviation
Therefore, s=10, which is the standard deviation
