Finding the Fourth Proportional to 9,905.79, 13,669.98 and 5,429.58

Step by Step Solution

1. Step 1: Write the proportion equation
   9,905.79 : 13,669.98 = 5,429.58 : x
2. Step 2: Convert to fraction form
   9,905.79/13,669.98 = 5,429.58/x
3. Step 3: Cross multiply
   9,905.79x = 13,669.98 × 5,429.58
4. Step 4: Simplify right side
   9,905.79x = 74,222,250.01
5. Step 5: Solve for x
   x = 74,222,250.01/9,905.79
6. Step 6: Final answer
   x = 7,492.81