1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
antiseptic1488 [7]
3 years ago
9

The radioisotope Mo-91 has a t1/2 of 15.5min. A sample decays at the rate of 954counts/min (954cpm). After how many minutes will

the decay be at 7.45cpm? (Step by step please)
Mathematics
1 answer:
TiliK225 [7]3 years ago
5 0

Step-by-step explanation:

Transcribed image text: Spectra Analysis 7 100 80 60 40 20 150 50 STRUCTURE 60 40 20 0 180 160 140 120 100 8O

You might be interested in
The value of 9−y is twice the value of y. What is the value of y?
ElenaW [278]

Answer:

y = 3

Step-by-step explanation:

9 - y = 2y

<u>Step 1:  Add y to both sides</u>

9 - y + y = 2y + y

9 = 3y

<u>Step 2:  Divide both sides by 3</u>

9 / 3 = 3y / 3

3 = y

Answer:  y = 3

7 0
3 years ago
Express sin Q as a fraction in simplest terms.​
Lesechka [4]

Answer:

Solution given

Sin Q=opposite/hypotenuse=28/29

<u>28/29</u><u> </u><u>is</u><u>. </u><u>a</u><u> </u><u>required</u><u> </u><u>answer</u><u>.</u><u />

3 0
3 years ago
Find the radian measure of the central angle of a circle of radius r that intercepts an arc of length s radius r 35 kilometers a
weeeeeb [17]

Answer:

Step-by-step explanation:

s=rtheta

s/r=theta

11.5/25=theta

theta=.46

3 0
3 years ago
Use technology or a z-score table to answer the question.
Alik [6]

Answer:

The second choice: Approximately 65.2\% of the pretzel bags here will contain between 225 and 245 pretzels.

Step-by-step explanation:

This explanation uses a z-score table where each z entry has two decimal places.

Let \mu represent the mean of a normal distribution of variable X. Let \sigma be the standard deviation of the distribution. The z-score for the observation x would be:

\displaystyle z = \frac{x - \mu}{\sigma}.

In this question,

  • \mu = 240.
  • \sigma = 9.3.

Calculate the z-score for x_1 = 225 and x_2 = 245. Keep in mind that each entry in the z-score table here has two decimal places. Hence, round the results below so that each contains at least two decimal places.

\begin{aligned} z_1 &= \frac{x_1 - \mu}{\sigma} \\ &= \frac{225 - 240}{9.3} \approx -1.61\end{aligned}.

\begin{aligned} z_2 &= \frac{x_2 - \mu}{\sigma} \\ &= \frac{245 - 240}{9.3} \approx 0.54\end{aligned}.

The question is asking for the probability P(225 \le X \le 245) (where X is between two values.) In this case, that's the same as P(-1.61 \le Z \le 0.54).

Keep in mind that the probabilities on many z-table correspond to probability of P(Z \le z) (where Z is no greater than one value.) Therefore, apply the identity P(z_1 \le Z \le z_2) = P(Z \le z_2) - P(Z \le z_1) to rewrite P(-1.61 \le Z \le 0.54) as the difference between two probabilities:

P(-1.61 \le Z \le 0.54) = P(Z \le 0.54) - P(Z \le -1.61).

Look up the z-table for P(Z \le 0.54) and P(Z \le -1.61):

  • P(Z \le 0.54)\approx 0.70540.
  • P(Z \le -1.61) \approx 0.05370.

\begin{aligned}& P(225 \le X \le 245) \\ &= P\left(\frac{225 - 240}{9.3} \le Z \le \frac{245 - 240}{9.3}\right)\\&\approx P(-1.61 \le Z \le 0.54) \\ &= P(Z \le 0.54) - P(Z \le -1.61)\\ &\approx 0.70540 - 0.05370 \\& \approx 0.65.2 \\ &= 65.2\% \end{aligned}.

3 0
3 years ago
How do you find a rate of a number
KATRIN_1 [288]

To determine the rate of a number do the following steps:


   Multiply the number by the percent (e.g. 87 * 68 = 5916)

   Divide the answer by 100 (Move decimal point two places to the left) (e.g. 5916/100 = 59.16)

   Round to the desired precision (e.g. 59.16 rounded to the nearest whole number = 59)

8 0
3 years ago
Read 2 more answers
Other questions:
  • How many 5-digit numbers can be formed using the digits 0, 1, 2, 3, 4, 5, 6, if repetition of digits is not allowed? a.119 b.16,
    15·1 answer
  • What is 50000x700? and 100x123,478
    7·2 answers
  • Boa tarde gentiii Abaixo aparecem quatro sequências. Defina cada uma delas como RECURSIVA ou NÃO RECURSIVA. a) (5, 7, 9, 11, 13,
    15·1 answer
  • You have a 12 inch by 14 inch picture that you frame. When you hung the picture, you found that the entire area is 261.44 in. Wh
    10·1 answer
  • Marcus has $40 in his pocket. Joseph has twice as much as Marcus, Jenna has half as much as Marcus, and Sam has one-third as muc
    15·2 answers
  • Three baseball players are playing catch. Vondra is directly south of Mei and directly west of
    11·1 answer
  • How many sides does a 1,260 degree polygon have?
    8·1 answer
  • Find the volume of the rectangular pyramid please help me guys
    8·2 answers
  • William is 11 years old. One day, his granddad took him and his younger brother to a basketball game. The tickets for the game w
    11·1 answer
  • Help Not sure .. does anyone have a clue ?
    7·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!