Can someone help me?
\[(4 - 1/3y) / (5/6y +1)\]
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the top divided by the bottom
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4 minus one third y divided by 5 over 6y plus 1
the first part is correct the second fraction is wrong
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\[4-\frac{ 1 }{ 3y }/\frac{ 5 }{ 6y }+1\]
\[\frac{ 4*3y-1 }{ 3y }/\frac{ 5+1*6y }{ 6y }\]
\[\frac{ 12y-1 }{ 3y }*\frac{ 6y }{ 5+6y }\]
\[\frac{ (12y-1)*2 }{ 5+6y }\]
\[\frac{ 24y-2 }{ 5+6y }\]
\( \Large{\dfrac{ 4 - \frac{1} {3y} } { \frac{5}{6y} + 1} }\) \( \Large{=\dfrac{ 4 - \frac{1} {3y} } { \frac{5}{6y} + 1} \cdot \dfrac{6y}{6y}}\) \( \Large{=\dfrac{ 24y - 2} { 5 + 6y} }\)
I am still confused where the extra 6y came in
@aliciabennett in which step u r confused?
the second
in second step , @mathstudent55 has multiplied and divide the whole term by the same number so that calculation can get more simpler for example - \[\frac{ 2 }{ 2 } = 1\] similarly, \[\frac{ 6y }{ 6y } = 1\]
I still don't get it :/
@aliciabennett The big fraction has a denominator of 3y in its numerator and a denominator of 6y in its denominator. The LCD of 3y and 6y is 6y. By multiplying the numerator and denominator of the big fraction by the LCD, 6y, you eliminate the fractions in the numerator and denominator. That helps you simplify the big fraction.
For example, look this problem: \( \dfrac{ \frac{1}{2} + 1}{ 2 - \frac{1}{3} } \) Once again you have a big fraction which has the fraction 1/2 in the numerator and the fraction 1/3 in the denominator. One way to simplify this fraction is to find the LCD of the denominators of the small fractions, 2 and 3. The LCD of 2 and 3 is 6. Now you multiply the entire fraction by 6/6. \(= \dfrac{ \frac{1}{2} + 1}{ 2 - \frac{1}{3} } \cdot \dfrac{6}{6}\) \( =\dfrac{ \frac{1}{2} \cdot 6+ 1 \cdot6}{ 2 \cdot 6- \frac{1}{3} \cdot 6 } \) \( =\dfrac{ 3 + 6}{ 12 - 2} \) \(= \dfrac{9}{10} \)
how do you do it without finding the LCD, how do you do it using the keep change flip method
@mathstudent55
Without simplifying with the LCD, you can use the method of dividing a fraction by a fraction: Remember that to divide a fraction by a fraction, you multiply the first fraction by the reciprocal of the second fraction. \(\Large{\dfrac{ 4 - \frac{1} {3y} } { \frac{5}{6y} + 1} }\) \(= \left(4 - \dfrac{1} {3y} \right) \div \left(\dfrac{5}{6y} + 1 \right)\) Now we need a common denominator for each factor.
but you can do the keep change flip method by flipping the 5/6y + 1 into 6y/5 +1
You can only do that when the denominator is written as a single fraction. That's what we're going to do now. We're going to use common denominators to make each factor in parentheses into a fraction. Then we can flip the second onend use multiplication.
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\(= \left(4 \cdot \dfrac{3y}{3y} - \dfrac{1} {3y} \right) \div \left(\dfrac{5}{6y} + 1 \cdot \dfrac{6y}{6y}\right)\) \(= \left( \dfrac{12y}{3y} - \dfrac{1} {3y} \right) \div \left(\dfrac{5}{6y} + \dfrac{6y}{6y}\right)\) \(= \left( \dfrac{12y - 1}{3y} \right) \div \left(\dfrac{5 + 6y} {6y}\right)\) Now both quantities are fractions, so we change the division to a multiplication by flipping the second fraction.
\(= \dfrac{12y - 1}{3y} \cdot \dfrac {6y} {5 + 6y} \) \(= \dfrac{12y - 1}{3y} \cdot \dfrac {2 \cdot 3y} {5 + 6y} \) \(= \dfrac{12y - 1}{\cancel{3y}} \cdot \dfrac {2 \cdot \cancel{3y}} {5 + 6y} \) \(= \dfrac{2(12y - 1)}{5 + 6y} \) \(= \dfrac{24y - 2}{5 + 6y} \)
That's how you'd do your first problem without multiplying by the LCD.
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