Finding the Fourth Proportional to 105,661.98, 145,817.16 and 57,915.30

Step by Step Solution

1. Step 1: Write the proportion equation
   105,661.98 : 145,817.16 = 57,915.30 : x
2. Step 2: Convert to fraction form
   105,661.98/145,817.16 = 57,915.30/x
3. Step 3: Cross multiply
   105,661.98x = 145,817.16 × 57,915.30
4. Step 4: Simplify right side
   105,661.98x = 8,445,044,566.55
5. Step 5: Solve for x
   x = 8,445,044,566.55/105,661.98
6. Step 6: Final answer
   x = 79,925.10