Finding the Third Proportional to 91,618.59 and 138,399.89

Step by Step Solution

1. Step 1: Write the proportion equation
   91,618.59 : 138,399.89 = 138,399.89 : x
2. Step 2: Convert to fraction form
   91,618.59/138,399.89 = 138,399.89/x
3. Step 3: Cross multiply
   91,618.59x = 138,399.89 × 138,399.89
4. Step 4: Simplify right side
   91,618.59x = 19,154,529,725.01
5. Step 5: Solve for x
   x = 19,154,529,725.01/91,618.59
6. Step 6: Final answer
   x = 209,068.15