Finding the Fourth Proportional to 11,901.60, 16,403.71 and 7,915.59

Step by Step Solution

1. Step 1: Write the proportion equation
   11,901.60 : 16,403.71 = 7,915.59 : x
2. Step 2: Convert to fraction form
   11,901.60/16,403.71 = 7,915.59/x
3. Step 3: Cross multiply
   11,901.60x = 16,403.71 × 7,915.59
4. Step 4: Simplify right side
   11,901.60x = 129,845,042.84
5. Step 5: Solve for x
   x = 129,845,042.84/11,901.60
6. Step 6: Final answer
   x = 10,909.88