Finding the Third Proportional to 9,966.80 and 21,878.86

Step by Step Solution

1. Step 1: Write the proportion equation
   9,966.80 : 21,878.86 = 21,878.86 : x
2. Step 2: Convert to fraction form
   9,966.80/21,878.86 = 21,878.86/x
3. Step 3: Cross multiply
   9,966.80x = 21,878.86 × 21,878.86
4. Step 4: Simplify right side
   9,966.80x = 478,684,487.55
5. Step 5: Solve for x
   x = 478,684,487.55/9,966.80
6. Step 6: Final answer
   x = 48,027.92