Finding the Third Proportional to 21,145.75 and 31,718.75

Step by Step Solution

1. Step 1: Write the proportion equation
   21,145.75 : 31,718.75 = 31,718.75 : x
2. Step 2: Convert to fraction form
   21,145.75/31,718.75 = 31,718.75/x
3. Step 3: Cross multiply
   21,145.75x = 31,718.75 × 31,718.75
4. Step 4: Simplify right side
   21,145.75x = 1,006,079,101.56
5. Step 5: Solve for x
   x = 1,006,079,101.56/21,145.75
6. Step 6: Final answer
   x = 47,578.31