Finding the Third Proportional to 640,155 and 991,147.50

Step by Step Solution

1. Step 1: Write the proportion equation
   640,155 : 991,147.50 = 991,147.50 : x
2. Step 2: Convert to fraction form
   640,155/991,147.50 = 991,147.50/x
3. Step 3: Cross multiply
   640,155x = 991,147.50 × 991,147.50
4. Step 4: Simplify right side
   640,155x = 982,373,366,756.25
5. Step 5: Solve for x
   x = 982,373,366,756.25/640,155
6. Step 6: Final answer
   x = 1,534,586.73