Finding the Third Proportional to 9,989.50 and 21,857.50

Step by Step Solution

1. Step 1: Write the proportion equation
   9,989.50 : 21,857.50 = 21,857.50 : x
2. Step 2: Convert to fraction form
   9,989.50/21,857.50 = 21,857.50/x
3. Step 3: Cross multiply
   9,989.50x = 21,857.50 × 21,857.50
4. Step 4: Simplify right side
   9,989.50x = 477,750,306.25
5. Step 5: Solve for x
   x = 477,750,306.25/9,989.50
6. Step 6: Final answer
   x = 47,825.25