Finding the Fourth Proportional to 105,513.88, 145,603.69 and 57,758.17

Step by Step Solution

1. Step 1: Write the proportion equation
   105,513.88 : 145,603.69 = 57,758.17 : x
2. Step 2: Convert to fraction form
   105,513.88/145,603.69 = 57,758.17/x
3. Step 3: Cross multiply
   105,513.88x = 145,603.69 × 57,758.17
4. Step 4: Simplify right side
   105,513.88x = 8,409,802,679.65
5. Step 5: Solve for x
   x = 8,409,802,679.65/105,513.88
6. Step 6: Final answer
   x = 79,703.28