Finding the Fourth Proportional to 278,931.52, 418,387.56 and 89,389.09

Step by Step Solution

1. Step 1: Write the proportion equation
   278,931.52 : 418,387.56 = 89,389.09 : x
2. Step 2: Convert to fraction form
   278,931.52/418,387.56 = 89,389.09/x
3. Step 3: Cross multiply
   278,931.52x = 418,387.56 × 89,389.09
4. Step 4: Simplify right side
   278,931.52x = 37,399,283,255.72
5. Step 5: Solve for x
   x = 37,399,283,255.72/278,931.52
6. Step 6: Final answer
   x = 134,080.52