Finding the Third Proportional to 399,303.75 and 865,980

Step by Step Solution

1. Step 1: Write the proportion equation
   399,303.75 : 865,980 = 865,980 : x
2. Step 2: Convert to fraction form
   399,303.75/865,980 = 865,980/x
3. Step 3: Cross multiply
   399,303.75x = 865,980 × 865,980
4. Step 4: Simplify right side
   399,303.75x = 749,921,360,400
5. Step 5: Solve for x
   x = 749,921,360,400/399,303.75
6. Step 6: Final answer
   x = 1,878,072.42