Finding the Fourth Proportional to 12,739.67, 17,580.16 and 7,074.78

Step by Step Solution

1. Step 1: Write the proportion equation
   12,739.67 : 17,580.16 = 7,074.78 : x
2. Step 2: Convert to fraction form
   12,739.67/17,580.16 = 7,074.78/x
3. Step 3: Cross multiply
   12,739.67x = 17,580.16 × 7,074.78
4. Step 4: Simplify right side
   12,739.67x = 124,375,835.72
5. Step 5: Solve for x
   x = 124,375,835.72/12,739.67
6. Step 6: Final answer
   x = 9,762.87