Finding the Third Proportional to 7,128 and 9,085.50

Step by Step Solution

1. Step 1: Write the proportion equation
   7,128 : 9,085.50 = 9,085.50 : x
2. Step 2: Convert to fraction form
   7,128/9,085.50 = 9,085.50/x
3. Step 3: Cross multiply
   7,128x = 9,085.50 × 9,085.50
4. Step 4: Simplify right side
   7,128x = 82,546,310.25
5. Step 5: Solve for x
   x = 82,546,310.25/7,128
6. Step 6: Final answer
   x = 11,580.57