Finding the Fourth Proportional to 12,558.56, 17,328.56 and 8,140

Step by Step Solution

1. Step 1: Write the proportion equation
   12,558.56 : 17,328.56 = 8,140 : x
2. Step 2: Convert to fraction form
   12,558.56/17,328.56 = 8,140/x
3. Step 3: Cross multiply
   12,558.56x = 17,328.56 × 8,140
4. Step 4: Simplify right side
   12,558.56x = 141,054,478.40
5. Step 5: Solve for x
   x = 141,054,478.40/12,558.56
6. Step 6: Final answer
   x = 11,231.74