When you have an equation that has variables and you know the value of those variables, just plug it it. So plugging the vaules we get Just evaluating we get 4
2 1/4 = 9/4 From mixed fraction to an improper fraction: "the numerator of the improper fraction" = "denominator" xx "the whole number" + "the numerator of the mixed fraction" The denominator remains as it is. So 2 1/4 = (4 xx 2 + 1)/4 = 9/4