Finding the Fourth Proportional to 11,769.72, 17,657.12 and 3,978.36

Step by Step Solution

1. Step 1: Write the proportion equation
   11,769.72 : 17,657.12 = 3,978.36 : x
2. Step 2: Convert to fraction form
   11,769.72/17,657.12 = 3,978.36/x
3. Step 3: Cross multiply
   11,769.72x = 17,657.12 × 3,978.36
4. Step 4: Simplify right side
   11,769.72x = 70,246,379.92
5. Step 5: Solve for x
   x = 70,246,379.92/11,769.72
6. Step 6: Final answer
   x = 5,968.40