Finding the Fourth Proportional to 15,494.53, 21,380.76 and 8,780.04

Step by Step Solution

1. Step 1: Write the proportion equation
   15,494.53 : 21,380.76 = 8,780.04 : x
2. Step 2: Convert to fraction form
   15,494.53/21,380.76 = 8,780.04/x
3. Step 3: Cross multiply
   15,494.53x = 21,380.76 × 8,780.04
4. Step 4: Simplify right side
   15,494.53x = 187,723,928.03
5. Step 5: Solve for x
   x = 187,723,928.03/15,494.53
6. Step 6: Final answer
   x = 12,115.50