Finding the Fourth Proportional to 28,469.34, 42,708.87 and 12,680.01

Step by Step Solution

1. Step 1: Write the proportion equation
   28,469.34 : 42,708.87 = 12,680.01 : x
2. Step 2: Convert to fraction form
   28,469.34/42,708.87 = 12,680.01/x
3. Step 3: Cross multiply
   28,469.34x = 42,708.87 × 12,680.01
4. Step 4: Simplify right side
   28,469.34x = 541,548,898.69
5. Step 5: Solve for x
   x = 541,548,898.69/28,469.34
6. Step 6: Final answer
   x = 19,022.18