Finding the Third Proportional to 258,090 and 391,014

Step by Step Solution

1. Step 1: Write the proportion equation
   258,090 : 391,014 = 391,014 : x
2. Step 2: Convert to fraction form
   258,090/391,014 = 391,014/x
3. Step 3: Cross multiply
   258,090x = 391,014 × 391,014
4. Step 4: Simplify right side
   258,090x = 152,891,948,196
5. Step 5: Solve for x
   x = 152,891,948,196/258,090
6. Step 6: Final answer
   x = 592,397.80