Finding the Fourth Proportional to 8,385.32, 12,587.20 and 7,085.16

Step by Step Solution

1. Step 1: Write the proportion equation
   8,385.32 : 12,587.20 = 7,085.16 : x
2. Step 2: Convert to fraction form
   8,385.32/12,587.20 = 7,085.16/x
3. Step 3: Cross multiply
   8,385.32x = 12,587.20 × 7,085.16
4. Step 4: Simplify right side
   8,385.32x = 89,182,325.95
5. Step 5: Solve for x
   x = 89,182,325.95/8,385.32
6. Step 6: Final answer
   x = 10,635.53