Finding the Third Proportional to 8,460 and 12,865.50

Step by Step Solution

1. Step 1: Write the proportion equation
   8,460 : 12,865.50 = 12,865.50 : x
2. Step 2: Convert to fraction form
   8,460/12,865.50 = 12,865.50/x
3. Step 3: Cross multiply
   8,460x = 12,865.50 × 12,865.50
4. Step 4: Simplify right side
   8,460x = 165,521,090.25
5. Step 5: Solve for x
   x = 165,521,090.25/8,460
6. Step 6: Final answer
   x = 19,565.14