Finding the Fourth Proportional to 9,912.17, 13,679.21 and 5,436.09

Step by Step Solution

1. Step 1: Write the proportion equation
   9,912.17 : 13,679.21 = 5,436.09 : x
2. Step 2: Convert to fraction form
   9,912.17/13,679.21 = 5,436.09/x
3. Step 3: Cross multiply
   9,912.17x = 13,679.21 × 5,436.09
4. Step 4: Simplify right side
   9,912.17x = 74,361,430.28
5. Step 5: Solve for x
   x = 74,361,430.28/9,912.17
6. Step 6: Final answer
   x = 7,502.03