Finding the Fourth Proportional to 28,290.72, 42,399.18 and 11,631.72

Step by Step Solution

1. Step 1: Write the proportion equation
   28,290.72 : 42,399.18 = 11,631.72 : x
2. Step 2: Convert to fraction form
   28,290.72/42,399.18 = 11,631.72/x
3. Step 3: Cross multiply
   28,290.72x = 42,399.18 × 11,631.72
4. Step 4: Simplify right side
   28,290.72x = 493,175,389.99
5. Step 5: Solve for x
   x = 493,175,389.99/28,290.72
6. Step 6: Final answer
   x = 17,432.41