Finding the Third Proportional to 15,172 and 21,782

Step by Step Solution

1. Step 1: Write the proportion equation
   15,172 : 21,782 = 21,782 : x
2. Step 2: Convert to fraction form
   15,172/21,782 = 21,782/x
3. Step 3: Cross multiply
   15,172x = 21,782 × 21,782
4. Step 4: Simplify right side
   15,172x = 474,455,524
5. Step 5: Solve for x
   x = 474,455,524/15,172
6. Step 6: Final answer
   x = 31,271.79