Finding the Fourth Proportional to 13,085.50, 18,057.97 and 7,117.18

Step by Step Solution

1. Step 1: Write the proportion equation
   13,085.50 : 18,057.97 = 7,117.18 : x
2. Step 2: Convert to fraction form
   13,085.50/18,057.97 = 7,117.18/x
3. Step 3: Cross multiply
   13,085.50x = 18,057.97 × 7,117.18
4. Step 4: Simplify right side
   13,085.50x = 128,521,822.92
5. Step 5: Solve for x
   x = 128,521,822.92/13,085.50
6. Step 6: Final answer
   x = 9,821.70