5/12 and 3/20
2007-09-13 09:41:02 · 4 answers · asked by baby166_99 2 in Science & Mathematics ➔ Mathematics
The lowest number that 12 and 20 will both go into is 60. So you have to change 12 into 60 by multiplying it by 5. You have to multiply the numerator by 5 as well, so:
5/12 x 5/5 = 25/60
You multiply 20 by 3 to get 60, and you have to multiply the numerator, 3, by 3 as well, so:
3/20 x 3/3 = 9/60.
If you think about this for a while, you`ll see that it`s the opposite process of cancelling.
Hope this helps, Twiggy.
2007-09-13 09:49:29 · answer #1 · answered by Twiggy 7 · 0⤊ 0⤋
LCD = 60
5/12 = 25/60 and 3/20 = 9/60
2007-09-13 16:52:56 · answer #2 · answered by ironduke8159 7 · 0⤊ 0⤋
Lowest common denominator = least common multiple of the denominators
In this case, we have 12 and 20
12 = 2^2 *3
20= 2^2 *5
Factors 2,3,5. So collect the terms, 2^2*3*5 = 60
So, sixty is the lowest common denominator.
5/12 = 5*5/12*5 = 25/60
3/20 = 3*3 / 20*3 = 9/60
Good luck!
2007-09-13 16:52:04 · answer #3 · answered by alrivera_1 4 · 0⤊ 0⤋
The LCD is 60:
25/60 and 9/60
2007-09-13 16:43:27 · answer #4 · answered by Kathryn 6 · 0⤊ 0⤋