Finding the Fourth Proportional to 28,238.27, 42,329.86 and 13,443.21

Step by Step Solution

1. Step 1: Write the proportion equation
   28,238.27 : 42,329.86 = 13,443.21 : x
2. Step 2: Convert to fraction form
   28,238.27/42,329.86 = 13,443.21/x
3. Step 3: Cross multiply
   28,238.27x = 42,329.86 × 13,443.21
4. Step 4: Simplify right side
   28,238.27x = 569,049,163.64
5. Step 5: Solve for x
   x = 569,049,163.64/28,238.27
6. Step 6: Final answer
   x = 20,151.70