Finding the Third Proportional to 5,421 and 12,499.50

Step by Step Solution

1. Step 1: Write the proportion equation
   5,421 : 12,499.50 = 12,499.50 : x
2. Step 2: Convert to fraction form
   5,421/12,499.50 = 12,499.50/x
3. Step 3: Cross multiply
   5,421x = 12,499.50 × 12,499.50
4. Step 4: Simplify right side
   5,421x = 156,237,500.25
5. Step 5: Solve for x
   x = 156,237,500.25/5,421
6. Step 6: Final answer
   x = 28,820.79