Finding the Fourth Proportional to 28,317.62, 42,471.20 and 13,116.62

Step by Step Solution

1. Step 1: Write the proportion equation
   28,317.62 : 42,471.20 = 13,116.62 : x
2. Step 2: Convert to fraction form
   28,317.62/42,471.20 = 13,116.62/x
3. Step 3: Cross multiply
   28,317.62x = 42,471.20 × 13,116.62
4. Step 4: Simplify right side
   28,317.62x = 557,078,591.34
5. Step 5: Solve for x
   x = 557,078,591.34/28,317.62
6. Step 6: Final answer
   x = 19,672.51