Step-by-step explanation:
Assuming the data is as shown, restaurant X has a mean service time of 180.56, with a standard deviation of 62.6.
The standard error is SE = s/√n = 62.6/√50 = 8.85.
At 95% confidence, the critical value is z = 1.960.
Therefore, the confidence interval is:
180.56 ± 1.960 × 8.85
180.56 ± 17.35
(163, 198)
Restaurant Y has a mean service time of 152.96, with a standard deviation of 49.2.
The standard error is SE = s/√n = 49.2/√50 = 6.96.
At 95% confidence, the critical value is z = 1.960.
Therefore, the confidence interval is:
152.96 ± 1.960 × 6.96
152.96 ± 13.64
(139, 167)
A.23/6
b.23/8
c.26/5
d.64/9
Answer:
Shawn is correct.
Step-by-step explanation:
Let the quadratic function is g(x) = a(x - h)² + k
Here (h, k) is the vertex of the parabola.
Since this parabola passes through (0, 0), (1, 9) and (-1, 9), axis of symmetry is x = 0 and the vertex is (0, 0).
Therefore, equation of the parabola will be,
g(x) = a(x - 0)²+ 0
g(x) = ax²
for a point (1, 9) which lies on the graph,
9 = a(1)²
a = 9
g(x) = 9x² (here a > 1)
Therefore, f(x) is vertically stretched by a factor of 9 to form g(x).
Shawn is correct.
55% of 1800 = 0.55(1800) = 990...so there are 990 girls in the school
30% of 990 = 0.30(990) = 297...so there are 297 girls who take the bus
Answer:
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Step-by-step explanation:
Given
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Required
Express in standard form
To do this, we simply reorder the terms of the polynomial in descending order of power.
So, we have:
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