Finding the Fourth Proportional to 12,978.67, 17,910.46 and 7,315.24

Step by Step Solution

1. Step 1: Write the proportion equation
   12,978.67 : 17,910.46 = 7,315.24 : x
2. Step 2: Convert to fraction form
   12,978.67/17,910.46 = 7,315.24/x
3. Step 3: Cross multiply
   12,978.67x = 17,910.46 × 7,315.24
4. Step 4: Simplify right side
   12,978.67x = 131,019,313.41
5. Step 5: Solve for x
   x = 131,019,313.41/12,978.67
6. Step 6: Final answer
   x = 10,094.97