Expand the fraction by the expansion number.

**Step 1: Calculate the numerator**

To calculate the new *numerator*, multiply the numerator of the fraction (1) by the expansion number (4):

Numerator = 1 × 4 = 4

**Step 2: Calculate the denominator**

To calculate the new *denominator*, multiply the denominator of the fraction (5) by the expansion number (4):

Denominator = 5 × 4 = 20