Finding the Fourth Proportional to 12,978.36, 17,895.90 and 8,779.32

Step by Step Solution

1. Step 1: Write the proportion equation
   12,978.36 : 17,895.90 = 8,779.32 : x
2. Step 2: Convert to fraction form
   12,978.36/17,895.90 = 8,779.32/x
3. Step 3: Cross multiply
   12,978.36x = 17,895.90 × 8,779.32
4. Step 4: Simplify right side
   12,978.36x = 157,113,832.79
5. Step 5: Solve for x
   x = 157,113,832.79/12,978.36
6. Step 6: Final answer
   x = 12,105.83