Three ventilation fans, each working alone, can clear the smoke out of a room in 12 hours, 16 hours, and 24 hours respectively. How long would it...
Answer:
Grades 6 and 8
Step-by-step explanation:
If the relationship of girls to boys in two different grades are proportional, <u>they must have the same ratio</u>. To tackle this problem, we can find the <u>ratios</u> of genders in each grade and compare them.
Step 1, finding ratios:
Finding ratios is just like <u>simplifying fractions</u>. We will reduce the numbers by their<u> greatest common factors</u>.




<u>Can't be simplified!</u>
<u />
Step 2:
Notice how grades 6 and 8 both had a ratio of 3:4. We can conclude that these two grades have a proportional relationship between girls and boys.
<em>I hope this helps! Let me know if you have any questions :)</em>
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Answer:
10
Step-by-step explanation:
you take 2 times 5
Markup means they sell it for that percentage more than they bought it for. First let's calculate how much they will mark it up for:

Convert 87% into a decimal(87/100):

Multiply:

This is how much they'll mark it up, now let's add it to how much they bought it for to find out the selling price:
Answer:Ax + By = C
-ax -ax
-------------------
By = -Ax + C
--- ------------
B B
--------------------
y = -Ax + C
----------
B
Step-by-step explanation: