Finding the Fourth Proportional to 9,990.49, 13,787.29 and 5,742.89

Step by Step Solution

1. Step 1: Write the proportion equation
   9,990.49 : 13,787.29 = 5,742.89 : x
2. Step 2: Convert to fraction form
   9,990.49/13,787.29 = 5,742.89/x
3. Step 3: Cross multiply
   9,990.49x = 13,787.29 × 5,742.89
4. Step 4: Simplify right side
   9,990.49x = 79,178,844.27
5. Step 5: Solve for x
   x = 79,178,844.27/9,990.49
6. Step 6: Final answer
   x = 7,925.42