Fractions in Real Life

A fraction shows a part of a whole. The bottom number (the denominator) tells you how many equal pieces the whole is cut into. The top number (the numerator) tells you how many of those pieces you have. So 3/4 of a pizza means the pizza was cut into 4 slices and you have 3 of them.

The bigger the bottom number, the smaller each piece. Think of cutting one cake for more guests: 1/8 of a cake is a smaller slice than 1/4, because eighths are tinier pieces than quarters. This is why 1/8 is less than 1/4, even though 8 looks bigger than 4. It helps to picture the pie, not just the numbers.

To compare two fractions, give them the same bottom number. To see whether 2/3 or 3/4 is bigger, rewrite both with a denominator of 12: 2/3 becomes 8/12, and 3/4 becomes 9/12. Now it's clear – 3/4 is the larger share. The number 12 works because both 3 and 4 divide into it evenly.

Fractions shine in the kitchen. Say a recipe serves 4 but you are cooking for 2. You want half, so you halve each amount. Half of 3/4 cup is 3/8 cup. If you don't have a 3/8 measure, just fill the 1/4 cup once, then add half of another 1/4. Doubling works the same way in reverse – two batches means twice every amount.

Fractions and decimals are two ways of saying the same thing. 1/2 is 0.5, 1/4 is 0.25, and 3/4 is 0.75. To turn any fraction into a decimal, divide the top by the bottom. This is handy when you split a bill: 1/3 of $60 is 60 divided by 3, which is $20 each.