Finding the Fourth Proportional to 12,420.89, 17,141.27 and 7,116.74

Step by Step Solution

1. Step 1: Write the proportion equation
   12,420.89 : 17,141.27 = 7,116.74 : x
2. Step 2: Convert to fraction form
   12,420.89/17,141.27 = 7,116.74/x
3. Step 3: Cross multiply
   12,420.89x = 17,141.27 × 7,116.74
4. Step 4: Simplify right side
   12,420.89x = 121,989,840.57
5. Step 5: Solve for x
   x = 121,989,840.57/12,420.89
6. Step 6: Final answer
   x = 9,821.35