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
Vlada [557]
3 years ago
8

Suppose that a chemist is mixing two acid​ solutions, one of 20​% concentration and the other of 30​% concentration. Which of th

e following concentrations could not be​ obtained?
1. 22​%,
2. 24​%,
3. 28​%,
4. 34​%
Mathematics
1 answer:
Pani-rosa [81]3 years ago
5 0

Answer:

4. 34%

Step-by-step explanation:

By mixing 20% and 30%, it will be between 20 and 30, like 22, 24 or 28. You would need a higher concentration than 30 to mix in to get 34%.

You might be interested in
Which equations represent the line that is parallel to 3x - 4y = 7 and passes through the point (-4,-2)? Select two
dem82 [27]

Answer:

3x - 4y = -4

Step-by-step explanation:

substitute the ordered pair into each equation and ensure that it comes out to be true.

8 0
3 years ago
The life of a red bulb used in a traffic signal can be modeled using an exponential distribution with an average life of 24 mont
BartSMP [9]

Answer:

See steps below

Step-by-step explanation:

Let X be the random variable that measures the lifespan of a bulb.

If the random variable X is exponentially distributed and X has an average value of 24 month, then its probability density function is

\bf f(x)=\frac{1}{24}e^{-x/24}\;(x\geq 0)

and its cumulative distribution function (CDF) is

\bf P(X\leq t)=\int_{0}^{t} f(x)dx=1-e^{-t/24}

• What is probability that the red bulb will need to be replaced at the first inspection?

The probability that the bulb fails the first year is

\bf P(X\leq 12)=1-e^{-12/24}=1-e^{-0.5}=0.39347

• If the bulb is in good condition at the end of 18 months, what is the probability that the bulb will be in good condition at the end of 24 months?

Let A and B be the events,

A = “The bulb will last at least 24 months”

B = “The bulb will last at least 18 months”

We want to find P(A | B).

By definition P(A | B) = P(A∩B)P(B)

but B⊂A, so  A∩B = B and  

\bf P(A | B) = P(B)P(B) = (P(B))^2

We have  

\bf P(B)=P(X>18)=1-P(X\leq 18)=1-(1-e^{-18/24})=e^{-3/4}=0.47237

hence,

\bf P(A | B)=(P(B))^2=(0.47237)^2=0.22313

• If the signal has six red bulbs, what is the probability that at least one of them needs replacement at the first inspection? Assume distribution of lifetime of each bulb is independent

If the distribution of lifetime of each bulb is independent, then we have here a binomial distribution of six trials with probability of “success” (one bulb needs replacement at the first inspection) p = 0.39347

Now the probability that exactly k bulbs need replacement is

\bf \binom{6}{k}(0.39347)^k(1-0.39347)^{6-k}

<em>Probability that at least one of them needs replacement at the first inspection = 1- probability that none of them needs replacement at the first inspection. </em>

This means that,

<em>Probability that at least one of them needs replacement at the first inspection =  </em>

\bf 1-\binom{6}{0}(0.39347)^0(1-0.39347)^{6}=1-(0.60653)^6=0.95021

5 0
3 years ago
If a=1.32332332...<br>b=0.101101110<br>&amp; 1/ac-bc=27 then what is c?​
Sever21 [200]

Answer:

are you trying to spam brainley

8 0
2 years ago
Angle 1 measure 75 degree what is its complement
dalvyx [7]
I think it’s 76 because I added it that’s a way i solved it but you can also multiple it by 1 and it will give the the same answer
3 0
3 years ago
PLEASE HELP I WILL GIVE BRAINLIST PLEASE
ivolga24 [154]

Answer: D: 4.5

Step-by-step explanation:

So the Equation I used for this would be

6(2x+3) = 3(6x-3)

In Which the left is the Hexagon (The 6 is for the 6 Sides) and the right of the equation is the triangle (given the 3 for the 3 sides. In order to solve, we need to solve for x. Distribute the equation and your left with

12x+18=18x-9

-12x            +9

27=6x

Divide to get X by itself

and your left with

4.5 = x

Hope it helped.

3 0
2 years ago
Other questions:
  • Hey can you please help me posted picture of question
    14·2 answers
  • When a fair coin is ossed 4 times what is probability of tossing at least 3 heads?
    12·1 answer
  • What is 8,450 ROUND. TO THE NEAREST THOUSAND
    13·2 answers
  • Given the following equation of an exponential function determine the decay rate.
    6·1 answer
  • if a toy rocket is launced vertically upward from ground level with an inital velocity of 128 feet per second, then its high h,
    5·1 answer
  • According to the graph, what is the value of the constant in the equation
    7·1 answer
  • I need help on similar triangles properties practice ​
    7·1 answer
  • Manuel makes 8 dollars for each hour of work. Write an equation to represent his total pay p after working h hours.
    8·2 answers
  • What is the exact value of 3.2²÷1.6-(3-8)?
    12·1 answer
  • | x | &lt; 2 <br><br> solve the inequality and then graph the solution
    10·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!