Finding the Fourth Proportional to 612,111.90, 857,656.50 and 612,111.90

Step by Step Solution

1. Step 1: Write the proportion equation
   612,111.90 : 857,656.50 = 612,111.90 : x
2. Step 2: Convert to fraction form
   612,111.90/857,656.50 = 612,111.90/x
3. Step 3: Cross multiply
   612,111.90x = 857,656.50 × 612,111.90
4. Step 4: Simplify right side
   612,111.90x = 524,981,749,762.35
5. Step 5: Solve for x
   x = 524,981,749,762.35/612,111.90
6. Step 6: Final answer
   x = 857,656.50