Fractions with Unlike Denominators

Master why we require common denominators. Visually slice two fractions into equal-sized units to add their segments.

Interactive Widget

Visual Fraction Partition Balancer

Select your fractions using the sliders. Note how Fraction A (Rose) and Fraction B (Cyan) have different subdivision block sizes. Drag the **Grid Density Selector** (Subdivision Denominator) below. Once both fractions' blocks align perfectly with the grid lines, they share a common unit division and can be combined!

Fraction A Numerator 1

Fraction A Denominator 2

Fraction B Numerator 1

Fraction B Denominator 3

Grid Density (Subdivision Denominator) 4

Fraction A Original vs Subdivided

1 2

→

? ?

Misaligned

Fraction B Original vs Subdivided

1 3

→

? ?

Misaligned

Addition Summation Formula

3 6

2 6

5 6

= 0.833

Grid lines must align with both fractions' borders to make addition valid. Drag the density slider to find the Lowest Common Multiple (e.g., 6).

If you pick denominator 6, the segments line up! That represents the Lowest Common Denominator (LCD).