Finding the Fourth Proportional to 10,306.72, 15,440.64 and 7,986.88

Step by Step Solution

1. Step 1: Write the proportion equation
   10,306.72 : 15,440.64 = 7,986.88 : x
2. Step 2: Convert to fraction form
   10,306.72/15,440.64 = 7,986.88/x
3. Step 3: Cross multiply
   10,306.72x = 15,440.64 × 7,986.88
4. Step 4: Simplify right side
   10,306.72x = 123,322,538.80
5. Step 5: Solve for x
   x = 123,322,538.80/10,306.72
6. Step 6: Final answer
   x = 11,965.26