Finding the Fourth Proportional to 402,084,564.72, 554,900,401.20 and 302,790,128.28

Step by Step Solution

1. Step 1: Write the proportion equation
   402,084,564.72 : 554,900,401.20 = 302,790,128.28 : x
2. Step 2: Convert to fraction form
   402,084,564.72/554,900,401.20 = 302,790,128.28/x
3. Step 3: Cross multiply
   402,084,564.72x = 554,900,401.20 × 302,790,128.28
4. Step 4: Simplify right side
   402,084,564.72x = 168,018,363,661,971,456
5. Step 5: Solve for x
   x = 168,018,363,661,971,456/402,084,564.72
6. Step 6: Final answer
   x = 417,868,225.75