Question

for some reason i keep getting the wrong answer for this fraction:
simplify.
(11/20 divided by 55/3) - (11/20 times 55/3)
this is the only one i keep missing for some reason.

Answer 1

Remember that when you divide a fraction, you multiply by its reciprocal

\(\Large (\frac{11}{20}\div \frac{55}{3})-(\frac{11}{20}\times\frac{55}{3})=(\frac{11}{20}\times\frac{3}{55})-(\frac{11}{20}\times\frac{55}{3})=?\)

Answer 2

yes i have that part down

Answer 3

Okay, so what do you get?

Answer 4

so far i got 33/1100 - 605/60

Answer 5

Things work out better when you don't multiply stuff together :)

Answer 6

Factor out the 11/20

Answer 7

Is that where you're headed @zepdrix ?

Answer 8

From your last step, I probably would have done a quick cancellation before moving forward.\[\large\rm \frac{\color{orangered}{11}\cdot3}{20\cdot\color{orangered}{55}}-\frac{11\cdot55}{20\cdot3}\]These orange pieces have something in common, yes?

Answer 9

yes

Answer 10

Yes, factoring works nicely as well :)
I don't think she's up to that point though.

Answer 11

Cancellation gives us,\[\large\rm \frac{\cancel{\color{orangered}{11}}\cdot3}{20\cdot\cancel{\color{orangered}{55}}5}-\frac{11\cdot55}{20\cdot3}\]

Answer 12

\[\large\rm \frac{3}{20\cdot5}-\frac{11\cdot55}{20\cdot3}\]I would STILL recommend not multiplying things out.
It's easier to see what each denominator is missing from this setup.
The first fraction is missing a 3,
while the second fraction is missing a 5, ya?

Answer 13

yes

Answer 14

\[\large\rm \color{royalblue}{\frac33}\cdot\frac{3}{20\cdot5}-\frac{11\cdot55}{20\cdot3}\cdot\color{royalblue}{\frac55}\]Which gives us something like,\[\large\rm \frac{3\cdot3}{20\cdot3\cdot5}-\frac{11\cdot55\cdot5}{20\cdot3\cdot5}\]Which we can combine into a single fraction, right?\[\large\rm \frac{3\cdot3-11\cdot55\cdot5}{20\cdot3\cdot5}\]And then it's probably safe to multiply things out from this point :)
And simplify.

Answer 15

When we do bigger fractions that involve more operations is it easier to do it the way we just did it ?

Answer 16

Maybe not always.
If you look at my last post,
that is a big mess of numbers, right?
If it becomes too much to carry around like that,
then I suppose you might reach a point where simplifying things down BEFORE proceeding forward makes more sense.

Though, leaving the denominator expanded out as I did will almost always better more beneficial. It just makes it way easier to see what each denominator is "missing".

Answer 17

makes sense. i know a lot of times when i try to work the whole thing out long ways i get confused by the numbers because it turns to a long process sometimes

Answer 18

hehe ya :))
try to get comfortable with AT LEAST leaving the bottoms expanded out.

math is tricky! but keep at it!
work hard! study! be blessed! :D

Answer 19

aww thank you i been trying my best and so far its doing me good !

Answer 20

good good good c:

Answer 21

thank you for helping me tonight :)

Answer 22

np