Finding the Fourth Proportional to 12,697.06, 17,519.86 and 7,978

Step by Step Solution

1. Step 1: Write the proportion equation
   12,697.06 : 17,519.86 = 7,978 : x
2. Step 2: Convert to fraction form
   12,697.06/17,519.86 = 7,978/x
3. Step 3: Cross multiply
   12,697.06x = 17,519.86 × 7,978
4. Step 4: Simplify right side
   12,697.06x = 139,773,443.08
5. Step 5: Solve for x
   x = 139,773,443.08/12,697.06
6. Step 6: Final answer
   x = 11,008.33