Answer: the extraction is 18.2%.
Explanation:
Let's see few definitions:
TDS = Total Dissolved Solids = solids dissolved in the brew
PE = Percent Extraction = percent of solids extracted from the dry coffee grounds
The percent extraction can be calculated by the formula:
PE = TDS × Rm
where
Rm = ratio between the mass of the brew and the mass of dry grounds
Now, you need to consider the following facts:
1) every 1g of coffee absorbs 2g of water
2) the given brew ratio is 1:15, which means that for every 1g of grounds we use 15g of water
Let's call
x = grams of coffee grounds we want to use
Therefore the mass of the brew will be:
m(brew) = water we use - water absorbed by the coffee
= 15·x - 2·x
= 13·x
Therefore,
Rm = m(brew) / x
= 13·x / x
= 13
Hence, the percent of extraction will be:
PE = <span> TDS × Rm
= 1.4 </span>× 13
= 18.2
The answer to this question would be C, 9. The reason for is cause you remove the parentheses then add the numbers 1.2 + 7.8=9.
Answer:
<h3>A) </h3>
First were going to put our numbers in perspective.
÷ 
But to find the improper fraction, we have to <em>cross multiply</em> these numbers.
×
<em>7 x 5 = 35. </em>
<em>4 x 8 = 32.</em>
Now we have our<em> improper fraction </em>is 
<h3>B) </h3>
To turn our improper fraction into a <em>mixed number</em>, we will use <em>division</em>.
We know that the 32 can only go into 35 <u><em>one</em></u> time. We also know that the bottom number <em><u>always</u></em> stays the same. So our equation will look somewhat like this.
Now to fine the top number we will have to<em> subtract 35 from 32</em> because we already know that 32 can go into 35 <u><em>one</em></u> time, so <em>35 - 32 = 3</em>. So are mixed number will look like this.
This is our <em>answer!</em>
5 x 1/4 = 1 1/4 or 1.25
4 x 1/2 = 2
1.25 + 2 = 3.25 or 3 and 1/4
