Finding the Third Proportional to 21,384 and 31,428

Step by Step Solution

1. Step 1: Write the proportion equation
   21,384 : 31,428 = 31,428 : x
2. Step 2: Convert to fraction form
   21,384/31,428 = 31,428/x
3. Step 3: Cross multiply
   21,384x = 31,428 × 31,428
4. Step 4: Simplify right side
   21,384x = 987,719,184
5. Step 5: Solve for x
   x = 987,719,184/21,384
6. Step 6: Final answer
   x = 46,189.64