Finding the Fourth Proportional to 105,513.12, 145,608.53 and 57,770.91

Step by Step Solution

1. Step 1: Write the proportion equation
   105,513.12 : 145,608.53 = 57,770.91 : x
2. Step 2: Convert to fraction form
   105,513.12/145,608.53 = 57,770.91/x
3. Step 3: Cross multiply
   105,513.12x = 145,608.53 × 57,770.91
4. Step 4: Simplify right side
   105,513.12x = 8,411,937,281.86
5. Step 5: Solve for x
   x = 8,411,937,281.86/105,513.12
6. Step 6: Final answer
   x = 79,724.09