Finding the Third Proportional to 10,815.75 and 11,947.50

Step by Step Solution

1. Step 1: Write the proportion equation
   10,815.75 : 11,947.50 = 11,947.50 : x
2. Step 2: Convert to fraction form
   10,815.75/11,947.50 = 11,947.50/x
3. Step 3: Cross multiply
   10,815.75x = 11,947.50 × 11,947.50
4. Step 4: Simplify right side
   10,815.75x = 142,742,756.25
5. Step 5: Solve for x
   x = 142,742,756.25/10,815.75
6. Step 6: Final answer
   x = 13,197.68