Answer:
i believe its the last one 2 x 10 = 20
Step-by-step explanation:
Use photomath
hope this helps
Hello,
1: 9n-3=21 ==>B
2: 3n+9=21 ==>A
3: 9n-3=21 ==>B
4: 3n-9=21 ==>C
I wish to have understood all those sentences.
The number of pounds of copper in 120 pounds of brass is = 78 pounds of copper
<h3>Calculation of number of pounds of copper</h3>
The percentage of copper in the brass = 65%
Therefore the quantity of copper in the brass = 65/100= 0.65 pounds
This means that 1 pound brass contains = 0.65 pounds of copper
The quantity of copper in 120 pounds of brass = 120 * 0.65
= 78 pounds of copper.
Learn more about copper here:
brainly.com/question/24856041
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