Finding the Fourth Proportional to 9,836.78, 13,543.40 and 9,166.10

Step by Step Solution

1. Step 1: Write the proportion equation
   9,836.78 : 13,543.40 = 9,166.10 : x
2. Step 2: Convert to fraction form
   9,836.78/13,543.40 = 9,166.10/x
3. Step 3: Cross multiply
   9,836.78x = 13,543.40 × 9,166.10
4. Step 4: Simplify right side
   9,836.78x = 124,140,045.19
5. Step 5: Solve for x
   x = 124,140,045.19/9,836.78
6. Step 6: Final answer
   x = 12,619.99