Gene spent one third hour writing an article for the school paper, and one fourth hour proofreading it. How long did Gene spend writing and proofreading his article? To find how long Gene spent writing and proofreading his paper, add one third hour and one fourth hour. Step one, write the problem. Step two, one third and one fourth are unlike fractions. Before you can add, you need to rename the fractions using the least common denominator. The least common denominator of one third and one fourth is twelve. Multiply the numerator and denominator of one third by four. So the new denominator is twelve. Multiply the numerator and denominator of one fourth by three, so the new denominator is twelve. Step three, four twelfths and three twelfths are like fractions. Add the numerators. Four twelfths plus three twelfths equals seven twelfths. So Gene spent seven twelfths hour writing and proofreading his article.
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