Is 3/4 Bigger Than 3/5?

Method 1: Common Denominators

To compare these fractions, we need a common denominator. The denominators are 4 and 5, and the least common denominator (LCD) is 20.

• Step 1. Convert \(\frac{3}{4}\): multiply numerator and denominator by 5.
  \[\frac{3}{4} = \frac{3 \times 5}{4 \times 5} = \frac{15}{20}\]
• Step 2. Convert \(\frac{3}{5}\): multiply numerator and denominator by 4.
  \[\frac{3}{5} = \frac{3 \times 4}{5 \times 4} = \frac{12}{20}\]
• Step 3. Compare the numerators: 15 vs 12.
• Step 4. Since 15 is greater than 12, we know that \(\frac{3}{4} > \frac{3}{5}\).

Method 2: Cross Multiplication

A quicker way to compare fractions is to cross-multiply. Multiply each numerator by the other fraction's denominator:

• Step 1. Multiply the numerator of the first fraction by the denominator of the second: \(3 \times 5 = 15\).
• Step 2. Multiply the numerator of the second fraction by the denominator of the first: \(3 \times 4 = 12\).
• Step 3. Compare the products: \(15 > 12\), so \(\frac{3}{4} > \frac{3}{5}\).

Method 3: Decimal Comparison

Convert each fraction to a decimal by dividing the numerator by the denominator:

Since 0.75 is greater than 0.6, we confirm that \(\frac{3}{4} > \frac{3}{5}\). In percentage terms, \(\frac{3}{4}\) is 75% and \(\frac{3}{5}\) is 60%, a difference of 15 percentage points.

Why Does This Work?

When two fractions have the same numerator, you have the same number of pieces — but the pieces are different sizes. A smaller denominator means each piece is larger. Since 5ths are larger pieces than 4ths, \(\frac{3}{4}\) is the bigger fraction even though both have 3 in the numerator.