Finding the Fourth Proportional to 3,978.54, 5,492.20 and 2,487.42

Step by Step Solution

1. Step 1: Write the proportion equation
   3,978.54 : 5,492.20 = 2,487.42 : x
2. Step 2: Convert to fraction form
   3,978.54/5,492.20 = 2,487.42/x
3. Step 3: Cross multiply
   3,978.54x = 5,492.20 × 2,487.42
4. Step 4: Simplify right side
   3,978.54x = 13,661,408.12
5. Step 5: Solve for x
   x = 13,661,408.12/3,978.54
6. Step 6: Final answer
   x = 3,433.77