Finding the Fourth Proportional to 420,196.50, 630,300.24 and 139,713.75

Step by Step Solution

1. Step 1: Write the proportion equation
   420,196.50 : 630,300.24 = 139,713.75 : x
2. Step 2: Convert to fraction form
   420,196.50/630,300.24 = 139,713.75/x
3. Step 3: Cross multiply
   420,196.50x = 630,300.24 × 139,713.75
4. Step 4: Simplify right side
   420,196.50x = 88,061,610,156.30
5. Step 5: Solve for x
   x = 88,061,610,156.30/420,196.50
6. Step 6: Final answer
   x = 209,572.45