Finding the Third Proportional to 311,980.50 and 493,578

Step by Step Solution

1. Step 1: Write the proportion equation
   311,980.50 : 493,578 = 493,578 : x
2. Step 2: Convert to fraction form
   311,980.50/493,578 = 493,578/x
3. Step 3: Cross multiply
   311,980.50x = 493,578 × 493,578
4. Step 4: Simplify right side
   311,980.50x = 243,619,242,084
5. Step 5: Solve for x
   x = 243,619,242,084/311,980.50
6. Step 6: Final answer
   x = 780,879.71