Finding the Fourth Proportional to 12,885.57, 17,778.63 and 7,779.83

Step by Step Solution

1. Step 1: Write the proportion equation
   12,885.57 : 17,778.63 = 7,779.83 : x
2. Step 2: Convert to fraction form
   12,885.57/17,778.63 = 7,779.83/x
3. Step 3: Cross multiply
   12,885.57x = 17,778.63 × 7,779.83
4. Step 4: Simplify right side
   12,885.57x = 138,314,719.03
5. Step 5: Solve for x
   x = 138,314,719.03/12,885.57
6. Step 6: Final answer
   x = 10,734.08