Finding the Fourth Proportional to 13,085.10, 18,057.51 and 7,778.88

Step by Step Solution

1. Step 1: Write the proportion equation
   13,085.10 : 18,057.51 = 7,778.88 : x
2. Step 2: Convert to fraction form
   13,085.10/18,057.51 = 7,778.88/x
3. Step 3: Cross multiply
   13,085.10x = 18,057.51 × 7,778.88
4. Step 4: Simplify right side
   13,085.10x = 140,467,203.39
5. Step 5: Solve for x
   x = 140,467,203.39/13,085.10
6. Step 6: Final answer
   x = 10,734.90