Finding the Third Proportional to 15,856.50 and 21,358.50

Step by Step Solution

1. Step 1: Write the proportion equation
   15,856.50 : 21,358.50 = 21,358.50 : x
2. Step 2: Convert to fraction form
   15,856.50/21,358.50 = 21,358.50/x
3. Step 3: Cross multiply
   15,856.50x = 21,358.50 × 21,358.50
4. Step 4: Simplify right side
   15,856.50x = 456,185,522.25
5. Step 5: Solve for x
   x = 456,185,522.25/15,856.50
6. Step 6: Final answer
   x = 28,769.62