Finding the Fourth Proportional to 612,196.10, 918,731.55 and 257,464.70

Step by Step Solution

1. Step 1: Write the proportion equation
   612,196.10 : 918,731.55 = 257,464.70 : x
2. Step 2: Convert to fraction form
   612,196.10/918,731.55 = 257,464.70/x
3. Step 3: Cross multiply
   612,196.10x = 918,731.55 × 257,464.70
4. Step 4: Simplify right side
   612,196.10x = 236,540,942,901.29
5. Step 5: Solve for x
   x = 236,540,942,901.29/612,196.10
6. Step 6: Final answer
   x = 386,381.00