Finding the Fourth Proportional to 12,657.72, 18,985.86 and 3,423

Step by Step Solution

1. Step 1: Write the proportion equation
   12,657.72 : 18,985.86 = 3,423 : x
2. Step 2: Convert to fraction form
   12,657.72/18,985.86 = 3,423/x
3. Step 3: Cross multiply
   12,657.72x = 18,985.86 × 3,423
4. Step 4: Simplify right side
   12,657.72x = 64,988,598.78
5. Step 5: Solve for x
   x = 64,988,598.78/12,657.72
6. Step 6: Final answer
   x = 5,134.31