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3 years ago

The half-life of a radioactive substance is 27.7 years.

Mathematics

1 answer:

Thepotemich [5.8K]3 years ago

6 0

Answer:

N(t) = N₀·0.5^(t/27.7)

11.5 years

242.5 grams

Step-by-step explanation:

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Guest ages at a ski mountain resort typically have a right-skewed distribution. Assume the standard deviation (σ) of age is 14.5

ValentinkaMS [17]

Answer: (30.49 years, 42.31 years)

Step-by-step explanation:

The formula to find the confidence interval is given by :-

$\overline{x}\pm z^*\dfrac{\sigma}{\sqrt{n}}.$

, where $\overline{x}$ = Sample mean

z* = Critical value.

$\sigma$ = Population standard deviation.

n= Sample size.

As per given , we have

$\overline{x}=36.4$

$\sigma=14.5$

n= 40

We know that the critical value for 99% confidence interval : z* = 2.576 (By z-table)

A 99 percent confidence interval for µ, the true mean age of guests will be :

$36.4\pm (2.576)\dfrac{14.5}{\sqrt{40}}\\\\ 36.4\pm (2.576)2.29265130362\\\\=36.4\pm5.90586975813\\\\\approx36.4\pm5.91\\\\=(36.4-5.91,\ 36.4+5.91)\\\\=(30.49,\ 42.31)$

∴ a 99 percent confidence interval for µ, the true mean age of guests = (30.49 years, 42.31 years)

7 0

3 years ago

Carissa has $250 in her checking account

exis [7]

Answer:

Step-by-step explanation:

8 0

3 years ago

Since it is given that AB ≅ AC, it must also be true that AB = AC. Assume ∠B and ∠C are not congruent. Then the measure of one a

BartSMP [9]

Answer: The required conclusion is

"if in triangle ABC, AB ≅ AC, then ∠B and ∠C must be congruent".

Step-by-step explanation: Given that in triangle ABC, AB ≅ AC, implies that AB = AC must be true. We are given to assume ∠B and ∠C are not congruent. Then the measure of one angle is greater than the other.

If m∠B > m∠C, then AC > AB because of the triangle parts relationship theorem.

For the same reason, if m∠B < m∠C, then AC < AB.

This is a contradiction to the given information.

We are to state the conclusion.

Since in the beginning, it is given that AB ≅ AC and we have assumed that ∠B and ∠C are not congruent, so

our assumption must be wrong.

That is, ∠B and ∠C must be congruent.

Thus, the required conclusion is

if in triangle ABC, AB ≅ AC, then ∠B and ∠C must be congruent.

5 0

3 years ago

Read 2 more answers