Finding the Fourth Proportional to 9,128.88, 13,680.72 and 4,737.60

Step by Step Solution

1. Step 1: Write the proportion equation
   9,128.88 : 13,680.72 = 4,737.60 : x
2. Step 2: Convert to fraction form
   9,128.88/13,680.72 = 4,737.60/x
3. Step 3: Cross multiply
   9,128.88x = 13,680.72 × 4,737.60
4. Step 4: Simplify right side
   9,128.88x = 64,813,779.07
5. Step 5: Solve for x
   x = 64,813,779.07/9,128.88
6. Step 6: Final answer
   x = 7,099.86