Finding the Fourth Proportional to 250,140,105.72, 345,193,378.65 and 138,638,145.20

Step by Step Solution

1. Step 1: Write the proportion equation
   250,140,105.72 : 345,193,378.65 = 138,638,145.20 : x
2. Step 2: Convert to fraction form
   250,140,105.72/345,193,378.65 = 138,638,145.20/x
3. Step 3: Cross multiply
   250,140,105.72x = 345,193,378.65 × 138,638,145.20
4. Step 4: Simplify right side
   250,140,105.72x = 47,856,969,749,631,304
5. Step 5: Solve for x
   x = 47,856,969,749,631,304/250,140,105.72
6. Step 6: Final answer
   x = 191,320,658.52