Finding the Third Proportional to 9,120 and 13,040.50

Step by Step Solution

1. Step 1: Write the proportion equation
   9,120 : 13,040.50 = 13,040.50 : x
2. Step 2: Convert to fraction form
   9,120/13,040.50 = 13,040.50/x
3. Step 3: Cross multiply
   9,120x = 13,040.50 × 13,040.50
4. Step 4: Simplify right side
   9,120x = 170,054,640.25
5. Step 5: Solve for x
   x = 170,054,640.25/9,120
6. Step 6: Final answer
   x = 18,646.34