Finding the Fourth Proportional to 1,387,676.10, 2,081,514.15 and 390,404.10

Step by Step Solution

1. Step 1: Write the proportion equation
   1,387,676.10 : 2,081,514.15 = 390,404.10 : x
2. Step 2: Convert to fraction form
   1,387,676.10/2,081,514.15 = 390,404.10/x
3. Step 3: Cross multiply
   1,387,676.10x = 2,081,514.15 × 390,404.10
4. Step 4: Simplify right side
   1,387,676.10x = 812,631,658,368.02
5. Step 5: Solve for x
   x = 812,631,658,368.02/1,387,676.10
6. Step 6: Final answer
   x = 585,606.15