Answer:
12.3
Step-by-step explanation:
Step 1
We find the mean
The data list shows the scores of ten students in Mr. Smith's math class. 61, 67, 81, 83, 87, 88, 89, 90, 98, 100
Mean = Sum of terms/Number of terms
Number of terms = 10
Mean = 61 + 67 + 81 + 83 + 87 + 88 + 89 + 90 + 98 + 100/10
Mean = 844/10
Mean = 84.4
Step 2
Standard deviation
The formula for sample standard deviation =
√(x - Mean)²/n - 1
= √[(61 - 84.4)² + (67 - 84.4)² + (81 - 84.4)² + (83 - 84.4)² + (87 - 84.4)² + (88 - 84.4)² + (89 - 84.4)² + (90 - 84.4)² + (98 - 84.4)² + (100 - 84.4)²]/10 - 1
=√ 547.56 + 302.76 + 11.56 + 1.96 + 6.76 + 12.96 + 21.16 + 31.36 + 184.96 + 243.36/10 - 1
= √1364.4/9
= √151.6
= 12.31259518
Approximately to the nearest tenth = 12.3
The standard deviation = 12.3
Answer:
1) 6m+8n
4) 21x+14y
7) 14c+16d
10) d+3e
Step-by-step explanation:
Answer:
1F
2C
3A
4E
5D
6B
Step-by-step explanation:
Good luck!
Answer:
The proportion of student heights that are between 94.5 and 115.5 is 86.64%
Step-by-step explanation:
We have a mean 
and a standard deviation 
. For a value x we compute the z-score as 
, so, for x = 94.5 the z-score is (94.5-105)/7 = -1.5, and for x = 115.5 the z-score is (115.5-105)/7 = 1.5. We are looking for P(-1.5 < z < 1.5) = P(z < 1.5) - P(z < -1.5) = 0.9332 - 0.0668 = 0.8664. Therefore, the proportion of student heights that are between 94.5 and 115.5 is 86.64%
Step-by-step explanation:
Use the method of TOA CAH SOH.
Perimeter of triangle = Sum of all sides =
