Finding the Fourth Proportional to 7,978.76, 11,975.06 and 7,960.31

Step by Step Solution

1. Step 1: Write the proportion equation
   7,978.76 : 11,975.06 = 7,960.31 : x
2. Step 2: Convert to fraction form
   7,978.76/11,975.06 = 7,960.31/x
3. Step 3: Cross multiply
   7,978.76x = 11,975.06 × 7,960.31
4. Step 4: Simplify right side
   7,978.76x = 95,325,150.07
5. Step 5: Solve for x
   x = 95,325,150.07/7,978.76
6. Step 6: Final answer
   x = 11,947.36