Here's how to subtract 5/11 from 3/7:
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Step 1We can't subtract two fractions with different denominators. So you need to get a common denominator. To do this, you'll multiply the denominators times each other... but the numerators have to change, too. They get multiplied by the other term's denominator. So we multiply 3 by 11, and get 33. Then we multiply 5 by 7, and get 35. Next we give both terms new denominators -- 7 × 11 = 77. So now our fractions look like this:
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Step 2Since our denominators match, we can subtract the numerators. 33 − 35 = -2 So the answer is:
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Step 3Last of all, we need to simplify the fraction, if possible. Can it be reduced to a simpler fraction? To find out, we try dividing it by 2... Nope! So now we try the next greatest prime number, 3... No good. 3 is larger than -2. So we're done reducing. There you have it! The final answer is:
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