How can you use improper fractions in real life?

Answer 1

Two simple examples are cooking and carpentry, at least in the US.

For cooking, suppose you needed to double a recipe that called for 3/4 of a cup of sugar. The new recipe would require 2 x 3/4 = 6/4 cups of sugar so you'd have to convert that to a proper fraction.

For carpentry, suppose you had to fasten a brace at the one-quarter, half, and three-quarter points of a wall opening that's 35½ inches wide. To divide 35½ by 4, you could convert the larger number to an improper fraction: 35 is the same as 70 halves, so adding the extra ½ gives you 71/2. Divide by 4 to get 71/8 and convert back to proper form: 71 ÷ 8 = 8-7/8 inches for the distance between the centers of each brace.

Of course if the US finally gives up ounces and inches in favor of metric units used everywhere else, most of these problems would be waaay simpler: The original recipe would need 175 gm of sugar so doubling would be 350 gm. The wall opening would be 900 mm so one-fourth would be 225 mm.