Finding the Third Proportional to 61,139.50 and 91,144.75

Step by Step Solution

1. Step 1: Write the proportion equation
   61,139.50 : 91,144.75 = 91,144.75 : x
2. Step 2: Convert to fraction form
   61,139.50/91,144.75 = 91,144.75/x
3. Step 3: Cross multiply
   61,139.50x = 91,144.75 × 91,144.75
4. Step 4: Simplify right side
   61,139.50x = 8,307,365,452.56
5. Step 5: Solve for x
   x = 8,307,365,452.56/61,139.50
6. Step 6: Final answer
   x = 135,875.59