Finding the Fourth Proportional to 445,111.76, 613,919.16 and 309,145.88

Step by Step Solution

1. Step 1: Write the proportion equation
   445,111.76 : 613,919.16 = 309,145.88 : x
2. Step 2: Convert to fraction form
   445,111.76/613,919.16 = 309,145.88/x
3. Step 3: Cross multiply
   445,111.76x = 613,919.16 × 309,145.88
4. Step 4: Simplify right side
   445,111.76x = 189,790,578,967.06
5. Step 5: Solve for x
   x = 189,790,578,967.06/445,111.76
6. Step 6: Final answer
   x = 426,388.60