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
vekshin1
3 years ago
7

We have two varieties of concrete that we can mix together. One is 5% water and 95% concrete mix, and the other is 20% water and

80% concrete mix. We want to end up with 30 pounds of a result that is 10% water and 90% concrete mix. Determine how many pounds of each variety we need.
Mathematics
1 answer:
Orlov [11]3 years ago
5 0

Answers:

  • <u>20 pounds</u> of the 95% concrete mix
  • <u>10 pounds</u> of the 80% concrete mix

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

Explanation:

x = amount of the 95% concrete mix

y = amount of the 80% concrete mix

Type A mix has 95% concrete. If we have x pounds of this, then 0.95x pounds is pure concrete. Type B mix has 80% concrete. If there are y pounds of this, then 0.80y pounds is pure concrete.

So far we have 0.95x+0.80y pounds of pure concrete from the two mixes

Divide this over 30 to get (0.95x+0.80y)/30

Setting this equal to 0.90 means we want the final mix to be 90% concrete.

Since we want 30 pounds total, we can say x+y = 30 which solves to y = 30-x. We'll use this later

-------------------------------

(0.95x+0.80y)/30 = 0.90

0.95x+0.80y = 30*0.90 .... multiply both sides by 30

0.95x+0.80y = 27

0.95x+0.80(30-x) = 27 ..... plug in y = 30-x

0.95x+0.80*30-0.80*x = 27

0.95x+24-0.80x = 27

0.15x+24 = 27

0.15x = 27-24 ..... subtracting 24 from both sides

0.15x = 3

x = 3/0.15 ........... dividing both sides by 0.15

x = 20

y = 30-x

y = 30-20

y = 10

You might be interested in
In triangle DEF, find m
marissa [1.9K]
You would have to share a picture or the details of this triangle in order for me to help
5 0
3 years ago
What is the value of x in the diagram?
Ksenya-84 [330]
The red arrows mean the lines are parallel. Since all angles are equal, the larger triangle is similar to the smaller one. Then corresponding sides have the same ratio
(4x -2)/9 = (3x+2)/12
x(4/9 -3/12) = (2/12) +(2/9)
x = (7/18)/(7/36) = 2 . . . . . . . . . corresponding to the 3rd selection
3 0
3 years ago
Helpppp plssssss and thxxx
velikii [3]

Answer:

x ≤ 13

Step-by-step explanation:

hope this helps

5 0
3 years ago
Read 2 more answers
If you were to roll the dice one time, what is the probability it will land on a 2?
vladimir2022 [97]

Answer:

1 out of 6

Step-by-step explanation:

6 0
3 years ago
Read 2 more answers
Fluency Practice 8x6= (8x5) + (8x__)=
Valentin [98]
The answer is 1.

8x6=48

8x5 + 8x1 = 48
4 0
3 years ago
Other questions:
  • A number changed to 193 after it was rounded
    7·2 answers
  • A car is traveling at 46 mph. it its tires have a diameter of 26 inches, how fast are the car's tires turning? express the answe
    13·1 answer
  • 11. Solve for the value of x in the triangle shown below. Show your work! (1 point for equation, 1 point for answer)
    15·1 answer
  • Please help me please
    8·2 answers
  • If a ray divides an angle into two complementary angles, then the original angle measures °
    11·2 answers
  • 8x-4y=16<br> -5x-5y=5<br> Graph the both
    8·2 answers
  • Solve the equation for Y<br> 2x + y = -9
    7·2 answers
  • What is the slope and y-intercept
    7·1 answer
  • Which fraction is equivalent to 2/4​
    8·2 answers
  • han want to buy a $30 ticket to a game, but the pre-oder tickets are sold out, he knowns there will be more tickets sold the day
    10·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!