Finding the Fourth Proportional to 12,561.34, 18,845.16 and 8,870.79

Step by Step Solution

1. Step 1: Write the proportion equation
   12,561.34 : 18,845.16 = 8,870.79 : x
2. Step 2: Convert to fraction form
   12,561.34/18,845.16 = 8,870.79/x
3. Step 3: Cross multiply
   12,561.34x = 18,845.16 × 8,870.79
4. Step 4: Simplify right side
   12,561.34x = 167,171,456.88
5. Step 5: Solve for x
   x = 167,171,456.88/12,561.34
6. Step 6: Final answer
   x = 13,308.41