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
Shtirlitz [24]
3 years ago
9

Can someone please help me on this problem? I tried setting it up but kept getting the wrong answer... Please help me!

Mathematics
1 answer:
Pani-rosa [81]3 years ago
6 0

Answer:

  • 240 mL of pure alcohol
  • 360 mL of 80% solution

Step-by-step explanation:

Let the variable (x) represent the amount of 100% alcohol that must be added. You want to find the amount of that such that the final solution will be 80% alcohol. We assume that we use the entire amount on hand of 40% mixture (see comment below).

  100%·x + 40%·120 = 80%·(x + 120)

  0.20x = 48 . . . . . . . simplify, subtract 48+0.80x

  48/0.20 = x = 240 . . . . . divide by the coefficient of x

___

You will need

240 mL of pure alcohol

to obtain

360 mL of the desired solution.

_____

<em>Comment on the problem</em>

The problem statement does not tell you how much solution is needed or how much of the 40% stock you're supposed to use. As a consequence, you can make any amount of desired 80% solution up to 360 mL. You could make 123 mL of 80% mix, for example. This means any pair of numbers will do for an answer as long as the second one is 3/2 times the first one. For <em>123 mL of mix</em>, you would need <em>82 mL of pure alcohol</em> to go with the 41 mL of 40% solution you would use.

_____

<em>Comment on mixture problem setup</em>

As a rule, the setup for a mixture problem is to add the contributions of the constituents and set that equal to the total amount in the mix. In this problem, each solution contributes some amount of alcohol. In "candy and nut" problems, each ingredient contributes some amount of cost to the total.

For this problem, the quantity of one of the ingredients is known. In some problems, you're to find the <em>two quantities</em> that result in some total. For those problems, you can set them up using two variables, with the <em>second equation</em> being the one that says the <em>total of the two quantities</em> is the specified amount.

You might be interested in
Is 1/2 √9 *√4 rational or irrational​
zloy xaker [14]

Answer:

1/2 and 9 is rational but 4 is not

Step-by-step explanation:

A rational number is a number that can be written as a ratio. That means it can be written as a fraction, in which both the numerator (the number on top) and the denominator (the number on the bottom) are whole numbers.

Hope this helps <3 Wanna get ranked faster? Comment "rankup"

6 0
2 years ago
Find the nth term <br> 26,19,12,5,-2<br><br> I will mark brainliest for the best answer :D
lara31 [8.8K]

Answer:

-9

Step-by-step explanation:

you're taking away 7 each time, so -2-7=-9

5 0
2 years ago
ILL BRAINLIEST YOU PLEASE HELP ME
liubo4ka [24]
15.8 I believe. Since 20 isn’t a option 15 is the closest. Good luck I have good faith I have you the right answer
8 0
3 years ago
Find the value of x.<br> 101 x +29
iVinArrow [24]

Answer:

x = 50

Step-by-step explanation:

101 + (x + 29) = 180

130 + x = 180

x = 180 - 130

x = 50

4 0
2 years ago
Read 2 more answers
Here is the question here please answer
earnstyle [38]

Daaaaaaaaaammmmm that’s hard

4 0
3 years ago
Other questions:
  • Round to the nearest cent or whole number as needed. The price of a candy bar is $0.82. If the tax rate is 8%, find the total co
    15·1 answer
  • whats the answer to -v+w=7 v+w=1 when this is a '' use elimination to solve each system of equations
    5·1 answer
  • What is the difference of 9/10 and 2/3
    5·2 answers
  • How many miles were ran?
    14·2 answers
  • QUICK! THIS QUESTION COULD BASICALLY FIT ALL SUBJECTS.
    8·1 answer
  • Find y. (leave answer in simplest radical form) *
    15·1 answer
  • In planning a Thanksgiving vacation, you want to rent a car for a week and travel the Pacific Highway from San Francisco to San
    6·1 answer
  • What is the relative frequency (to the nearest percent) of boys among those who cannot bike to school
    9·1 answer
  • Х = 2y + 3<br> х = Зу — 4​
    11·2 answers
  • A deck of cards contains 5 black cards numbered 5 to 9 and 5 red cards numbered 1 to 5. How many 6-card hands having 4 black car
    9·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!