Finding the Third Proportional to 260,379 and 390,568.50

Step by Step Solution

1. Step 1: Write the proportion equation
   260,379 : 390,568.50 = 390,568.50 : x
2. Step 2: Convert to fraction form
   260,379/390,568.50 = 390,568.50/x
3. Step 3: Cross multiply
   260,379x = 390,568.50 × 390,568.50
4. Step 4: Simplify right side
   260,379x = 152,543,753,192.25
5. Step 5: Solve for x
   x = 152,543,753,192.25/260,379
6. Step 6: Final answer
   x = 585,852.75