Finding the Third Proportional to 170,478 and 260,907.75

Step by Step Solution

1. Step 1: Write the proportion equation
   170,478 : 260,907.75 = 260,907.75 : x
2. Step 2: Convert to fraction form
   170,478/260,907.75 = 260,907.75/x
3. Step 3: Cross multiply
   170,478x = 260,907.75 × 260,907.75
4. Step 4: Simplify right side
   170,478x = 68,072,854,010.06
5. Step 5: Solve for x
   x = 68,072,854,010.06/170,478
6. Step 6: Final answer
   x = 399,305.80