Finding the Third Proportional to 279,135 and 398,695.50

Step by Step Solution

1. Step 1: Write the proportion equation
   279,135 : 398,695.50 = 398,695.50 : x
2. Step 2: Convert to fraction form
   279,135/398,695.50 = 398,695.50/x
3. Step 3: Cross multiply
   279,135x = 398,695.50 × 398,695.50
4. Step 4: Simplify right side
   279,135x = 158,958,101,720.25
5. Step 5: Solve for x
   x = 158,958,101,720.25/279,135
6. Step 6: Final answer
   x = 569,466.75