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
oksano4ka [1.4K]
4 years ago
13

There are 6 chemical elements represented by Li, Na, Mg, Rb, Cs, and Fr that

Mathematics
2 answers:
Bumek [7]4 years ago
5 0

Answer:

1/6

Step-by-step explanation:

I think this is tricky.

when you randomly choose the 1st two times, it doesn't matter as long as Na was not chosen, otherwise the probability would become ZERO for the 3rd one be Na.

So, after 1st two is removed, there are only 4 left in the pool, so picking Na at the 3rd draw is 1/4 probability.

But, come to think of it, when 1st draw, you have to draw the other 5 out of 6, 2nd draw the 4 out of 5, then 3rd is 1 Na out of the 4.

So, 5/6 x 4/5 x 1/4 = 1/6

serg [7]4 years ago
4 0
The answer is going to be 1/6
You might be interested in
(CESGRANRIO) Determine o parâmetro m na equação x²+mx+m²-m-12=0, de modo que ela tenha uma raíz nula e outra positiva.
slavikrds [6]
Vamos lá. 

<span>Pede-se para determinar o parâmetro "m" da equação abaixo, sabendo-se que uma raiz é nula e a outra é positiva: </span>

<span>x² + mx + m² - m - 12 = 0 </span>

<span>Veja que se uma raiz é nula (é igual a zero), então vamos substituir o "x" por "0", na equação acima: </span>

<span>0² + m*0 + m² - m - 12 = 0 </span>
<span>0 + 0 + m² - m - 12 = 0 </span>
<span>m² - m - 12 = 0 ------resolvendo essa equação do 2º grau você encontrará as seguintes raízes: </span>

<span>m' = -3 </span>
<span>m'' = 4 </span>

<span>Dessa forma, vamos substituir "m" por (-3) e por 4 e ver se a equação terá uma raiz nula e outra positiva. Vamos ver? </span>

<span>Substituindo "m" por "-3", ficamos com: </span>

<span>x² - 3x + (-3)² - (-3) - 12 = 0 </span>
<span>x² - 3x + 9 + 3 - 12 = 0 </span>
<span>x² - 3x +12 - 12 = 0 </span>
<span>x² - 3x = 0 <------Veja que as raízes dessa equação são: x' = 0 e x'' = 3 </span>
<span>Veja que para m = -3, a equação se verifica, pois temos uma raiz igual a "0" e a outra positiva (igual a 3). </span>

<span>Agora vamos substituir "m" por 4 na equação original: </span>

<span>x² + 4x + 4² - 4 - 12 = 0 </span>
<span>x² + 4x + 16 - 16 = 0 </span>
<span>x² + 4x = 0 <----- Veja que as raízes dessa equação são: x' = 0 e x'' = -4. </span>
<span>Observe que, para m = 4, a equação NÃO se verifica, pois temos uma raiz igual a "0" e a outra negativa (igual a -4). E no enunciado é informado que uma raiz deverá ser nula e a outra positiva. Como deu uma nula e a outra negativa, então m = 4 não convém. </span>

<span>Logo, o valor de "m" deverá ser: </span>

<span>m = -3 <----Pronto. Essa é a resposta. </span>
4 0
3 years ago
PLS HELP
-BARSIC- [3]

Answer:

I believe the answer would be 32.64

Step-by-step explanation:

$24 x 36% = 8.64

8.64 + 24 = $32.64

7 0
2 years ago
Math geometry show work Thanks
aev [14]

Problem 1, part (a)

<h3>Answer: False</h3>

For instance, 200 feet in real life can be reduced to scale down to say 2 inches on paper. So we have a reduction going on, and not an enlargement.

====================================================

Problem 1, part (b)

<h3>Answer: true</h3>

This is because a scale drawing involves similar polygons. This is true whenever any dilation is applied.

====================================================

Problem 2

I'm not sure how your teacher wanted you to answer this question. S/he didn't give you any numbers for the side lengths of the polygon. The angle measures are missing as well.

4 0
3 years ago
How do you convert a fraction to a percent
Lubov Fominskaja [6]
To convert from a fraction to a percent,
You just need to divide the fractions then multiply the product by 100.

Examples:
1. What is 3/4 in percent?
a. 3/4 = 0.75 x 100 = 75%
b. 45/98 = 0.46 x 100 = 46&
c. 60/100 = 0.6 x 100 = 60%
d. 1/5 = 0.2 x 100 = 20&
e. 6/99 = 0.06 x 100 = 6%
3 0
3 years ago
Someone help me ASAP!!!! I need this ASAP!!!!
qwelly [4]
So to solve it the equation is a squared plus b squared = c squared. So you square a and b. Then do the square root of that and should get c. C is always the largest side. C is opposite from a 90 degree angle . Hope this helps you answer your question.
5 0
3 years ago
Other questions:
  • Joey went to the Walmart and brought 5 skateboards. He spent a total of 115$. How much does each skateboard cost
    5·2 answers
  • Please help, I don't understand it
    9·2 answers
  • Eliza wants to conduct a survey to find out how much time students from her school spend listening to music. Which of the follow
    5·1 answer
  • Suppose one of your friends was absent from school on the day your math class learned about graphing rational numbers on the num
    6·2 answers
  • Find the sum of the first 15 terms of the arithmetic of the sequence where the 1st term is 3200 and the common difference is 150
    7·1 answer
  • Plz help on 55 if you can!!
    13·2 answers
  • Confounding
    14·1 answer
  • IF Triangle DEF JKL, find KL.
    8·1 answer
  • I need help please <br><br> x+y&gt;1
    13·1 answer
  • There are 32 different bowls of ice cream at an ice cream parlor. How many ways can you select three of them for a bowl of ice c
    12·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!