(9-243)/(4-1)=-78
D)−78 contestants per round, and it represents the average rate at which the number of contestants changed from the first round to the fourth roundReport · <span>14/12/2015</span>
Answer:
2cnd one 3rd one 4th one last one
Step-by-step explanation:
Answer:
the simplest form of 15/20 is 3/4
2(2x − 1) > 6 or x + 3 ≤ −6
2(2x − 1) > 6
4x - 2 > 6
4x > 8
x > 2
or
x + 3 ≤ −6
x ≤ - 9
Solution: x ≤ - 9 or x > 2
(- ∞ , - 9] or (2 , + ∞)
Answer is the first one
(- ∞ , - 9] or (2 , + ∞)
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
