## Rebecca* Can someone please explaine ratios and solving proportions? Thanksss(: one year ago one year ago

1. Rudy

Ratios and proportions are fractions. Remember equivalent fractions? 1/2 =2/4=5/10=14/28 Well ratios are fractions, and since they're usually maintained, you can compare different values as long as you keep the same ratio. Do you have a specific problem to look at?

2. Rebecca*

um, 18/20 K/110... it says to use cross products! What is that?

3. Rebecca*

@Rudy

4. Rudy

So your ratio is 18/20 and since a ratio is maintained, you can say that it equals k/110 so: $\frac{18}{20}=\frac{k}{110}$ Which you can solve as any equation. To isolate k, multiply times 110 on both sides. $\frac{18*110}{20}=\frac{k*110}{110}$ $\frac{18*110}{20}=k$

5. Rebecca*

there are others but i woll try my best on them! I just dont under stand this one!

6. Rebecca*

*Will

7. Rebecca*

so its 1,800?

8. Rebecca*

haha, thats way off!

9. Rudy

Just remember a ratio is maintained. So you can equate the ratios given, no matter the change in the amount... Like unit prices. If someone says a quart of oil is 3.25 how many can you buy with 22.75 Well the fraction is: $\frac{quarts of oil}{price}=\frac{1}{3.25}=\frac{x - quarts}{22.75}$ Hope that helps. Let me know if you have any you're stuck on, I may take time to answer, but I will.

10. Rebecca*

oh!! So thats the cross thing? Not that hard, thank you so much!! All of them are alike!! haha, thanks so much!!|dw:1355342436738:dw|

11. Rudy

you're welcome.