Finding the Fourth Proportional to 861,084,870.29, 1,291,815,677.90 and 278,877,968.77

Step by Step Solution

1. Step 1: Write the proportion equation
   861,084,870.29 : 1,291,815,677.90 = 278,877,968.77 : x
2. Step 2: Convert to fraction form
   861,084,870.29/1,291,815,677.90 = 278,877,968.77/x
3. Step 3: Cross multiply
   861,084,870.29x = 1,291,815,677.90 × 278,877,968.77
4. Step 4: Simplify right side
   861,084,870.29x = 360,258,932,270,139,072
5. Step 5: Solve for x
   x = 360,258,932,270,139,072/861,084,870.29
6. Step 6: Final answer
   x = 418,377,960.99