Finding the Third Proportional to 8,911 and 12,970.50

Step by Step Solution

1. Step 1: Write the proportion equation
   8,911 : 12,970.50 = 12,970.50 : x
2. Step 2: Convert to fraction form
   8,911/12,970.50 = 12,970.50/x
3. Step 3: Cross multiply
   8,911x = 12,970.50 × 12,970.50
4. Step 4: Simplify right side
   8,911x = 168,233,870.25
5. Step 5: Solve for x
   x = 168,233,870.25/8,911
6. Step 6: Final answer
   x = 18,879.35