Finding the Fourth Proportional to 9,912.59, 13,679.55 and 5,436.30

Step by Step Solution

1. Step 1: Write the proportion equation
   9,912.59 : 13,679.55 = 5,436.30 : x
2. Step 2: Convert to fraction form
   9,912.59/13,679.55 = 5,436.30/x
3. Step 3: Cross multiply
   9,912.59x = 13,679.55 × 5,436.30
4. Step 4: Simplify right side
   9,912.59x = 74,366,150.49
5. Step 5: Solve for x
   x = 74,366,150.49/9,912.59
6. Step 6: Final answer
   x = 7,502.19