Finding the Fourth Proportional to 85,417.63, 127,249.50 and 81,579.49

Step by Step Solution

1. Step 1: Write the proportion equation
   85,417.63 : 127,249.50 = 81,579.49 : x
2. Step 2: Convert to fraction form
   85,417.63/127,249.50 = 81,579.49/x
3. Step 3: Cross multiply
   85,417.63x = 127,249.50 × 81,579.49
4. Step 4: Simplify right side
   85,417.63x = 10,380,949,312.76
5. Step 5: Solve for x
   x = 10,380,949,312.76/85,417.63
6. Step 6: Final answer
   x = 121,531.69