Finding the Fourth Proportional to 12,422.16, 17,142.12 and 8,891.28

Step by Step Solution

1. Step 1: Write the proportion equation
   12,422.16 : 17,142.12 = 8,891.28 : x
2. Step 2: Convert to fraction form
   12,422.16/17,142.12 = 8,891.28/x
3. Step 3: Cross multiply
   12,422.16x = 17,142.12 × 8,891.28
4. Step 4: Simplify right side
   12,422.16x = 152,415,388.71
5. Step 5: Solve for x
   x = 152,415,388.71/12,422.16
6. Step 6: Final answer
   x = 12,269.64