Finding the Fourth Proportional to 28,443.20, 42,669.84 and 13,642.16

Step by Step Solution

1. Step 1: Write the proportion equation
   28,443.20 : 42,669.84 = 13,642.16 : x
2. Step 2: Convert to fraction form
   28,443.20/42,669.84 = 13,642.16/x
3. Step 3: Cross multiply
   28,443.20x = 42,669.84 × 13,642.16
4. Step 4: Simplify right side
   28,443.20x = 582,108,784.45
5. Step 5: Solve for x
   x = 582,108,784.45/28,443.20
6. Step 6: Final answer
   x = 20,465.66