Finding the Fourth Proportional to 105,557.58, 145,665.54 and 57,811.32

Step by Step Solution

1. Step 1: Write the proportion equation
   105,557.58 : 145,665.54 = 57,811.32 : x
2. Step 2: Convert to fraction form
   105,557.58/145,665.54 = 57,811.32/x
3. Step 3: Cross multiply
   105,557.58x = 145,665.54 × 57,811.32
4. Step 4: Simplify right side
   105,557.58x = 8,421,117,145.91
5. Step 5: Solve for x
   x = 8,421,117,145.91/105,557.58
6. Step 6: Final answer
   x = 79,777.47