Finding the Fourth Proportional to 31,580.76, 47,353.72 and 12,856

Step by Step Solution

1. Step 1: Write the proportion equation
   31,580.76 : 47,353.72 = 12,856 : x
2. Step 2: Convert to fraction form
   31,580.76/47,353.72 = 12,856/x
3. Step 3: Cross multiply
   31,580.76x = 47,353.72 × 12,856
4. Step 4: Simplify right side
   31,580.76x = 608,779,424.32
5. Step 5: Solve for x
   x = 608,779,424.32/31,580.76
6. Step 6: Final answer
   x = 19,276.91