Finding the Third Proportional to 4,821 and 7,978.50

Step by Step Solution

1. Step 1: Write the proportion equation
   4,821 : 7,978.50 = 7,978.50 : x
2. Step 2: Convert to fraction form
   4,821/7,978.50 = 7,978.50/x
3. Step 3: Cross multiply
   4,821x = 7,978.50 × 7,978.50
4. Step 4: Simplify right side
   4,821x = 63,656,462.25
5. Step 5: Solve for x
   x = 63,656,462.25/4,821
6. Step 6: Final answer
   x = 13,204.00