Finding the Fourth Proportional to 105,131.91, 145,079.76 and 57,386.07

Step by Step Solution

1. Step 1: Write the proportion equation
   105,131.91 : 145,079.76 = 57,386.07 : x
2. Step 2: Convert to fraction form
   105,131.91/145,079.76 = 57,386.07/x
3. Step 3: Cross multiply
   105,131.91x = 145,079.76 × 57,386.07
4. Step 4: Simplify right side
   105,131.91x = 8,325,557,262.94
5. Step 5: Solve for x
   x = 8,325,557,262.94/105,131.91
6. Step 6: Final answer
   x = 79,191.53