Finding the Fourth Proportional to 128,788.18, 177,710.76 and 71,426.82

Step by Step Solution

1. Step 1: Write the proportion equation
   128,788.18 : 177,710.76 = 71,426.82 : x
2. Step 2: Convert to fraction form
   128,788.18/177,710.76 = 71,426.82/x
3. Step 3: Cross multiply
   128,788.18x = 177,710.76 × 71,426.82
4. Step 4: Simplify right side
   128,788.18x = 12,693,314,466.58
5. Step 5: Solve for x
   x = 12,693,314,466.58/128,788.18
6. Step 6: Final answer
   x = 98,559.62