Plz answer its 5th grade math

A chemist has one solution that has 50% acid. She has another solution that is 25% acid. How many liters of the 50% acid solutio

Tatiana [17]

Answer:

Step-by-step explanation:

Let's begin by assigning letters to represent our two unknowns:

x (liters of 25% solution)

y (liters of 50% solution)

Our system of equations will consist of two equations:

Equation #1 (total volume of solution)

Equation #2 (total concentration of acid)

Our total volume of solution is 10 liters, which can be expressed as the sum of our unknowns:

Equation #1: x + y = 10

Our total concentration of acid can be expressed as the sum of the individual acid concentrations to make up the concentration of the final solution:

Equation #2: (0.25)(x) + (0.50)(y) =

(0.40)(10)

We can use Equation #1 to express one unknown in terms of the other and then plug that expression into Equation #2 to solve for one of the unknowns:

x + y = 10

y = 10 - x

Now we'll plug our expression for y in terms of x into Equation #2 and solve for x:

0.25(x) + 0.50(10 - x) = 0.40(10)

0.25x + 5 - 0.50x = 4

-0.25x = 4 - 5

-0.25x = -1

x = (-1)/(-0.25)

x = 4 (liters of 25% solution)

Now we'll plug our value for x into Equation #1 and solve for y:

4 + y = 10

y = 10 - 4

y = 6 (liters of 50% solution)

Finally, we will verify the correctness of our answers by plugging these values into Equation #2 to see if the sum of the component acid concentrations equals the final solution concentration:

0.25(4) + (0.50)(6) = 0.40(10)

1 + 3 = 4

4 = 4 (our answers are correct)

8 0

2 years ago

The expression below represents the number of bacteria in a petri dish after t hours. Interpret the meaning of the expression.

konstantin123 [22]

The answer is B) The initial number of bacteria is 57, and the growth rate is 31% per hour.

The expression shown is an exponential expression. An exponential expression usually takes the form $ab^{x}$ , as this one does. A represents the initial value, in this case-the initial number of bacteria. B represents the growth rate. When it is an increasing growth rate, it will begin with 1, because it will have everything it had before, plus the percent increase, the decimal portion. In this case, a=57, and b=0.31.

Hope this makes sense!

3 0

3 years ago

What are three ordered pairs that have a proportional relationship

MaRussiya [10]

1-3
2-6
3-9 This is an example of porportional.

1-4
2-3
3-9 There is no pattern so thin is Non-Porportional.

7 0

3 years ago

Please help me thank you so much. Just not sure of my answers

Sedaia [141]

Answer:

An interesting experiment is given. We need to address various questions based on our knowledge of calculus.

Step 2

Part (a)

Time taken for the radius to grow to 2 cm = t1 = r/0.5 = 2/0.5 = 4 hours

Time taken for the radius to become 0 = t2 and the same can be obtained by solving:

r = 2 - √t2 = 0

Hence, t2 = 22 = 4 hours

Hence, the time duration of the entire experiment (from the introduction of the bacteria until its disappearance) = t1 + t2 = 4 + 4 = 8 hours

Step 3

Part (b)

r(t) = 0.5t for 0 ≤ t ≤ 4

and

r(t) = 2 - √(t - 4) for t > 2

Step-by-step explanation:

7 0

3 years ago

How to solve 3x/7 - 1/2 = 1/14

nlexa [21]

Answer: 4/3

Step-by-step explanation:

First off, we should all get the denominators to be the same.

14 is the LCM of each of the denominators, so:

3x / 7 times 2/2 = 6x/14

-1/2 times 7/7 = -7/14

and 1/14 is 1/14

So now we have

6x/7 + -7/14 = 1/14

We can multiply everything by 14 to get rid of the denominator completely, which leaves us with:

6x - 7 = 1

Then we just solve like a normal equation:

6x = 8

x = 8/6 , or 4/3

8 0

3 years ago

Plz answer its 5th grade math​

Plz answer its 5th grade math