Finding the Fourth Proportional to 11,085.72, 16,628.67 and 7,813.50

Step by Step Solution

1. Step 1: Write the proportion equation
   11,085.72 : 16,628.67 = 7,813.50 : x
2. Step 2: Convert to fraction form
   11,085.72/16,628.67 = 7,813.50/x
3. Step 3: Cross multiply
   11,085.72x = 16,628.67 × 7,813.50
4. Step 4: Simplify right side
   11,085.72x = 129,928,113.05
5. Step 5: Solve for x
   x = 129,928,113.05/11,085.72
6. Step 6: Final answer
   x = 11,720.31