Shamar has 215 photos on his cell phone. He deletes some so that only 129 photos remain. What is the percent decrease in the num
1 answer:
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Answer:
39.5 ft
Step-by-step explanation:
The mnemonic SOH CAH TOA reminds you of the relation between angles and sides of a right triangle.
Tan = Opposite/Adjacent
This lets us write two equations in two unknowns:
tan(67°) = AD/CD . . . . . . . . . . angle at guy point
tan(39°) = AD/(CD+32) . . . . . .angle 32' farther
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Solving the first equation for CD and using that in the second equation, we can get an equation for AD, the height of the tower.
CD = AD/tan(67°)
tan(39°)(CD +32) = AD . . . . eliminate fractions in the second equation
tan(39°)(AD/tan(67°) +32) = AD
32·tan(39°) = AD(1 -tan(39°)/tan(67°)) . . . simplify, subtract left-side AD term
32·tan(39°)tan(67°)/(tan(67°) -tan(39°)) = AD . . . . divide by AD coefficient
AD ≈ 39.486 . . . . feet
The tower is about 39.5 feet high.
Answer:
Yes, it would be statistically significant
Step-by-step explanation:
The information given are;
The percentage of jawbreakers it produces that weigh more than 0.4 ounces = 60%
Number of jawbreakers in the sample, n = 800
The mean proportion of jawbreakers that weigh more than 0.4 = 60% = 0.6 = =p
The formula for the standard deviation of a proportion is
Solving for the standard deviation gives;
Given that the mean proportion is 0.6, the expected value of jawbreakers that weigh more than 0.4 in the sample of 800 = 800*0.6 = 480
For statistical significance the difference from the mean = 2× = 2*0.0173 = 0.0346 the equivalent number of Jaw breakers = 800*0.0346 = 27.7
The z-score of 494 jawbreakers is given as follows;
Therefore, the z-score more than 2 × which is significant.