Finding the Third Proportional to 66,609.50 and 139,377

Step by Step Solution

1. Step 1: Write the proportion equation
   66,609.50 : 139,377 = 139,377 : x
2. Step 2: Convert to fraction form
   66,609.50/139,377 = 139,377/x
3. Step 3: Cross multiply
   66,609.50x = 139,377 × 139,377
4. Step 4: Simplify right side
   66,609.50x = 19,425,948,129
5. Step 5: Solve for x
   x = 19,425,948,129/66,609.50
6. Step 6: Final answer
   x = 291,639.30