-4(3x-5)
-12x+20
Please vote my answer brainliest!
The jar has 138 grams of zinc.
<u>Solution:</u>
Given that , In a certain chemical reaction, the ratio of zinc to copper is 3 to 16.
A jar of the chemical contains 736 grams of copper.
We have to find how many grams of zinc does it contain
Let "n" be the grams of zinc needed for 736 grams of copper
Now, we know that,
16 grams of copper ⇒ 3 grams of zinc
Then, 736 grams of copper ⇒ n grams of zinc
So, by criss cross multiplication,

16n = 3 x 736
16n = 2208
n = 138
Hence, the jar has 138 grams of zinc.
The answer actually is 4,245 BUT that is the correct way to do it because you take the smaller population away from the larger population in order to find their difference in sizes.
You have the right idea and you are close to the correct answer. However that's not what your teacher is looking for in terms of steps.
The starting inequality is

She starts off selling 8 buckets. Then she sells b more to get a total of b+8
This total must be 20 or larger which is why I set b+8 greater than or equal to 20
Solve for b by subtracting 8 from both sides



So she needs to sell at least 12 more buckets to reach her goal
If you graphed this on a number line, then you would draw a closed circle at 12. Then shade to the right of the close circle.