2006-11-27 13:58:33 · 3 answers · asked by Anonymous in Science & Mathematics ➔ Medicine
21*4=84
3*7=21
84/21=4
2006-11-27 14:02:14 · answer #1 · answered by hockey 2 · 0⤊ 0⤋
You multiply fractions by taking the product of the top numbers (numerators) as the new numerator and the product of the bottom numbers (denominators) as the new denominator. So you would multiply 21 by 4 to get 84, and multiply 3 by 7 to get 21. The answer is 84/21. Then you can simplify it by dividing both the top and the bottom by 21, to get 4/1. And because the bottom number is 1, there's no need to write it as a fraction, so your final answer is 4.
2006-11-27 14:02:43 · answer #2 · answered by Amy F 5 · 0⤊ 0⤋
Multiplying fractions is easy:
Multiply everything above, and multiply everything below the bar:
21*4
------
3*7
This is 21*4 / 21, so you can get rid of 21/21 and get the end result: 4.
2006-11-27 14:03:54 · answer #3 · answered by Anonymous · 0⤊ 0⤋