Finding the Fourth Proportional to 28,239.93, 42,366.72 and 8,517.29

Step by Step Solution

1. Step 1: Write the proportion equation
   28,239.93 : 42,366.72 = 8,517.29 : x
2. Step 2: Convert to fraction form
   28,239.93/42,366.72 = 8,517.29/x
3. Step 3: Cross multiply
   28,239.93x = 42,366.72 × 8,517.29
4. Step 4: Simplify right side
   28,239.93x = 360,849,428.76
5. Step 5: Solve for x
   x = 360,849,428.76/28,239.93
6. Step 6: Final answer
   x = 12,777.99