Finding the Third Proportional to 11,428 and 15,870

Step by Step Solution

1. Step 1: Write the proportion equation
   11,428 : 15,870 = 15,870 : x
2. Step 2: Convert to fraction form
   11,428/15,870 = 15,870/x
3. Step 3: Cross multiply
   11,428x = 15,870 × 15,870
4. Step 4: Simplify right side
   11,428x = 251,856,900
5. Step 5: Solve for x
   x = 251,856,900/11,428
6. Step 6: Final answer
   x = 22,038.58