Finding the Third Proportional to 3,478.78 and 7,387.88

Step by Step Solution

1. Step 1: Write the proportion equation
   3,478.78 : 7,387.88 = 7,387.88 : x
2. Step 2: Convert to fraction form
   3,478.78/7,387.88 = 7,387.88/x
3. Step 3: Cross multiply
   3,478.78x = 7,387.88 × 7,387.88
4. Step 4: Simplify right side
   3,478.78x = 54,580,697.02
5. Step 5: Solve for x
   x = 54,580,697.02/3,478.78
6. Step 6: Final answer
   x = 15,689.60