Finding the Third Proportional to 120.19 and 259.59

Step by Step Solution

1. Step 1: Write the proportion equation
   120.19 : 259.59 = 259.59 : x
2. Step 2: Convert to fraction form
   120.19/259.59 = 259.59/x
3. Step 3: Cross multiply
   120.19x = 259.59 × 259.59
4. Step 4: Simplify right side
   120.19x = 67,388.92
5. Step 5: Solve for x
   x = 67,388.92/120.19
6. Step 6: Final answer
   x = 560.70