Another strategy that works fine here is cross multiplying. It goes as follows: 6(5 - 4r) - 8(2 - 3r/8 x 6. That gives: 30 - 24r - 16 + 24r/48 => 14/48 = 7/24.
step one get the lowest common denominator. This case 24. Step two rewrite as 15/24 - 12r/24 + -8/24 + 12r/24. We had a minus minus here so we rewrite the second fraction to opposite signs. Positive becomes negative and negative becomes positive. The r term is removed since we have (-12r/24) + (12r/24). (Remember zero times any thing is zero and zero divided by anything is also zero. ) step three combine remaining terms. (15/24) - (8/24) = 7/24 Super simple if you got it wrong you need to study harder.
Got it with the bow tie method, then I verified my equation and had a change of heart. To make sure 7/24 was the right result I double checked. I came up after cross multiplying with (30 - 24r) - (16 -24r)/48 At first I cancelled 24r but it left me with 30 - (-16), so I changed my answer for 46/48 or 23/24. :( I need to do it again with the bow tie to figure out what I did wrong. I guess I should have read the equation like this: -24r - (-24r) = -minus 24 r + 24r. Then I was left with 30 - 16. That would make sense.
r is subtracted out kind of. Once both fractions have the same denominator, you can add/subtract across both numerators. So -12r + 12r cancel each other out so we no longer have the variable r. Sorry if that is a bad explanation, I am learning too :)
@@brendanleonard1375 Thank you for your input. I got it that 12r - 12 r = 0. And I just figured out you can delete all the r's in the beginning, like this 5/8 - 2/6 = 15/24 - 8/24 = 7/24. It means that r = 0, doesn't it?
12r-12r=0, reduces to 0r=0, which shows that r=0/0. 0/0 is undefined, so you can say that r could have any value. In fact it disappears in the problem so its value doesn't influence the @nswer.
7/24. First, you need a common denominator. The LCM of 6 and 8 is 24, which is 6x4 and 8x3. Now, you multiply the numerator by the multiplier. 3(5-4r)=15-12r. 4(2-3r)=8-12r. Therefore we have (15-12r/24)-(8-12r/24). Add 12r to both sides. Now we have (15/24)-(8/24). We do this, and get the answer 7/24.
wrong you didn't divide 15 by 24 The proper writing is ((15 - 12r) / 24) - ((8 - 12r)/24) Of course I am sure this is an error only because you couldn't write it out on pc like you can on paper, but it is still wrong.
i wrote in the comment section of one of his problems i wonder how many of his students have fallen asleep from boredom because he takes forever to get to the answer.
Another strategy that works fine here is cross multiplying. It goes as follows: 6(5 - 4r) - 8(2 - 3r/8 x 6. That gives: 30 - 24r - 16 + 24r/48 => 14/48 = 7/24.
step one get the lowest common denominator. This case 24.
Step two rewrite as 15/24 - 12r/24 + -8/24 + 12r/24. We had a minus minus here so we rewrite the second fraction to opposite signs. Positive becomes negative and negative becomes positive. The r term is removed since we have (-12r/24) + (12r/24). (Remember zero times any thing is zero and zero divided by anything is also zero. )
step three combine remaining terms. (15/24) - (8/24) = 7/24
Super simple if you got it wrong you need to study harder.
That was a good refresher.
I did it differently. In order to get a common denominator I cross multiplied 6/6 and 8/8 both are ones
I noticed that -4r/8 and -(-3r/6) net to 0 (-r/2 and r/2),
so the equation becomes: 5/8 - 1/3 = (15-8)/24 = 7/24.
Got it with the bow tie method, then I verified my equation and had a change of heart. To make sure 7/24 was the right result I double checked.
I came up after cross multiplying with (30 - 24r) - (16 -24r)/48
At first I cancelled 24r but it left me with 30 - (-16), so I changed my answer for 46/48 or 23/24. :(
I need to do it again with the bow tie to figure out what I did wrong.
I guess I should have read the equation like this: -24r - (-24r) = -minus 24 r + 24r. Then I was left with 30 - 16. That would make sense.
got it 7/24 cross multiplied and reduced thanks for an easy one
Not as easy as you think. Your answers incorrect
You just proved the author was correct in his assumption
But still taking too long
Another bone. Thanks Boss.
You need to find the least common denominator or LCD to do this problem for starters .
Did r disappear? Can I substitute r with anything in the beginning and the result will always be 7/24?
r is subtracted out kind of. Once both fractions have the same denominator, you can add/subtract across both numerators. So -12r + 12r cancel each other out so we no longer have the variable r. Sorry if that is a bad explanation, I am learning too :)
@@brendanleonard1375 Thank you for your input. I got it that 12r - 12 r = 0. And I just figured out you can delete all the r's in the beginning, like this 5/8 - 2/6 = 15/24 - 8/24 = 7/24. It means that r = 0, doesn't it?
12r-12r=0, reduces to 0r=0, which shows that r=0/0. 0/0 is undefined, so you can say that r could have any value. In fact it disappears in the problem so its value doesn't influence the @nswer.
7/24
14-9r
14-9r/24
7/24.
First, you need a common denominator. The LCM of 6 and 8 is 24, which is 6x4 and 8x3.
Now, you multiply the numerator by the multiplier. 3(5-4r)=15-12r.
4(2-3r)=8-12r.
Therefore we have
(15-12r/24)-(8-12r/24).
Add 12r to both sides. Now we have (15/24)-(8/24).
We do this, and get the answer 7/24.
wrong you didn't divide 15 by 24
The proper writing is ((15 - 12r) / 24) - ((8 - 12r)/24)
Of course I am sure this is an error only because you couldn't write it out on pc like you can on paper, but it is still wrong.
@@bigdog3628 yeah I think that’s what I meant, but the answer still ends up the same.
7
I got it right again 😂❤
i wrote in the comment section of one of his problems i wonder how many of his students have fallen asleep from boredom because he takes forever to get to the answer.
Ok 7/24
5- 4ŕ/8 - 2-3r/6 = 15 - 12r /24 + -8 +12r/24 = 15-12r+12r /24 + -8 + 12r - 12r/ 24 = 15 - 8/ 24 = 7/24 th sorry started watching the Olympics and forgot to send
Loosing variable usually bad🤦🏻♂️
Ans.7/24
7/24
7/24
7/24
7/24