Finding the Fourth Proportional to 9,156.06, 12,644.32 and 7,821.98

Step by Step Solution

1. Step 1: Write the proportion equation
   9,156.06 : 12,644.32 = 7,821.98 : x
2. Step 2: Convert to fraction form
   9,156.06/12,644.32 = 7,821.98/x
3. Step 3: Cross multiply
   9,156.06x = 12,644.32 × 7,821.98
4. Step 4: Simplify right side
   9,156.06x = 98,903,618.15
5. Step 5: Solve for x
   x = 98,903,618.15/9,156.06
6. Step 6: Final answer
   x = 10,801.98