Finding the Third Proportional to 13,989.38 and 21,120.75

Step by Step Solution

1. Step 1: Write the proportion equation
   13,989.38 : 21,120.75 = 21,120.75 : x
2. Step 2: Convert to fraction form
   13,989.38/21,120.75 = 21,120.75/x
3. Step 3: Cross multiply
   13,989.38x = 21,120.75 × 21,120.75
4. Step 4: Simplify right side
   13,989.38x = 446,086,080.56
5. Step 5: Solve for x
   x = 446,086,080.56/13,989.38
6. Step 6: Final answer
   x = 31,887.49