Lines a and b are parallel. What is the measure of ∠5 if ∠4 measures 104°?

How long will it take before twenty percent of our 1,000-gram sample of uranium-235 has decayed? [See Section 6.6 Example 13] Th

horsena [70]

Answer:

From what I can see of the problem, you CANNOT solve for the half-life of U 235 AND then solve for the length of time to determine the 20% decay.

U-235 half-life is 704,000,000 years. (Wikipedia)

The elapsed time formula = half-life * [log (Beginning Amount / ending amount) / log 2]

elapsed time = 7.04 x 10^8 * [log (100 % / 80%) / log 2]

elapsed time =7.04 x 10^8 * [log (1.25) / .30103]

elapsed time =7.04 x 10^8 * [0.096910 / .30103]

elapsed time = 7.04 x 10^8 * 0.321928047

elapsed time = 226,637,000 years

Step-by-step explanation:

8 0

2 years ago

What’s 8/15 divided by 4/5

iragen [17]

Answer: 2/3

Step-by-step explanation: In this problem, we have 8/15 ÷ 4/5. Dividing by a fraction is the same as multiplying by its reciprocal. In other words, we can change the division sign to multiplication and flip the second fraction.

8/15 ÷ 4/5 can be rewritten as 8/15 × 5/4

Now, we are simply multiplying fractions so we multiply across the numerators and multiply across the denominators.

8/15 × 5/4 = 40/60 = 2/3

8 0

2 years ago

A university warehouse has received a shipment of 25 printers, of which 10 are laser printers and 15 are inkjet models. If 6 of

Tanya [424]

Answer:

The probability is 0.31

Step-by-step explanation:

To find the probability, we will consider the following approach. Given a particular outcome, and considering that each outcome is equally likely, we can calculate the probability by simply counting the number of ways we get the desired outcome and divide it by the total number of outcomes.

In this case, the event of interest is choosing 3 laser printers and 3 inkjets. At first, we have a total of 25 printers and we will be choosing 6 printers at random. The total number of ways in which we can choose 6 elements out of 25 is $\binom{25}{6}$ , where $\binom{n}{k} = \frac{n!}{(n-k)!k!}$ . We have that $\binom{25}{6} = 177100$

Now, we will calculate the number of ways to which we obtain the desired event. We will be choosing 3 laser printers and 3 inkjets. So the total number of ways this can happen is the multiplication of the number of ways we can choose 3 printers out of 10 (for the laser printers) times the number of ways of choosing 3 printers out of 15 (for the inkjets). So, in this case, the event can be obtained in $\binom{10}{3}\cdot \binom{15}{3} = 54600$

So the probability of having 3 laser printers and 3 inkjets is given by

$\frac{54600}{177100} = \frac{78}{253} = 0.31$

4 0

2 years ago

When performing a horizontal analysis on an income statement, the percentage change in any individual item is calculated by div

oksian1 [2.3K]

Answer: C. the base period amount.

Explanation: While implementing a horizontal analysis on a given income statement, we compute a percentage change in any individual item by dividing the dollar amount of change from base to current time period with the base period amount.

i.e. % Change in Individual item = $\frac{Current\ Dollar\ - Base\ Dollar }{Base \ period \ amount}$

Therefore, the correct option in this case is (c)

4 0

2 years ago

A sequence is defined by the recursive function f(n + 1) = -

Sauron [17]

Answer:

100

Step-by-step explanation:

f(n+1)=-10 f(n)

f(1)=1

put n=1

f(2)=-10f(1)=-10×1=-10

put n=2

f(3)=-10f(2)=-10×-10=100

5 0

2 years ago