Answer:
The mean speed of the automobiles traveling on this road is the closest to 65 mph.
Step-by-step explanation:
frequency distribution of speeds.
Speed (mph) | Frequency
45 up to 55 | 70
55 up to 65 | 360
65 up to 75 | 250
75 up to 85 | 110
Using the midpoint method, we represent each group/class of speeds with the midpoint speed, then go ahead to compute the mean.
Let the speed be x
The frequency be f
x | f
50 | 70
60 | 360
70 | 250
80 | 110
Mean = (Σfx)/(Σf)
Σfx = (50×70) + (60×360) + (70×250) + (80×110) = 51,400
Σf = 70 + 360 + 250 + 110 = 790
Mean = (Σfx)/(Σf)
Mean = (51400/790) = 65.06 mph ≈ 65 mph
The mean speed of the automobiles traveling on this road is the closest to 65 mph
Hope this Helps!!!
Answer:
$30.00 i think?
Step-by-step explanation:
$100 x 30 = $30.00
The confidence interval for a <span>(1−α)%</span> confidence level is given by
<span>
(<span>θ0</span>−<span>Z<span>α/2 </span></span><span>σ/√n</span>, <span>θ0</span>+<span>Z<span>α/2 </span></span><span>σ/√n</span>)
</span><span>θ0</span> is the measured statistic, <span>Z<span>α/2</span></span> is the cutoff/critical value, and <span>σ/<span>√n</span></span> is the standard error. σ is the population standard deviation (if known) or can be estimated by a sample standard deviation. n is the sample size.
The cutoff value depends on the test you wish to use, and <span>θ0</span><span> depends on the statistic you wish to estimate.</span>
Answer:
Total surface area of the prism = 920 cm²
Step-by-step explanation:
Given prism has 2 similar triangular surfaces and 3 rectangular surfaces of different dimensions.
Area of one triangular side = 
Area of 2 similar sides = Base × Height
= 8 × 15
= 120 cm²
Area of rectangular side with dimensions 17cm × 20cm
Area of the side = 17 × 20 = 340 cm²
Area of the second rectangular side with dimensions 8cm × 20cm
Area of the side = 8 × 20 = 160 cm²
Area of third rectangular side with dimensions 20cm × 15cm
Area of the side = 20 × 15 = 300 cm²
Total surface area of the given triangular prism = 120 + 340 + 160 + 300
= 920 cm²