Finding the Third Proportional to 91,389 and 138,055.50

Step by Step Solution

1. Step 1: Write the proportion equation
   91,389 : 138,055.50 = 138,055.50 : x
2. Step 2: Convert to fraction form
   91,389/138,055.50 = 138,055.50/x
3. Step 3: Cross multiply
   91,389x = 138,055.50 × 138,055.50
4. Step 4: Simplify right side
   91,389x = 19,059,321,080.25
5. Step 5: Solve for x
   x = 19,059,321,080.25/91,389
6. Step 6: Final answer
   x = 208,551.59