Finding the Fourth Proportional to 9,991.16, 13,787.55 and 5,514.90

Step by Step Solution

1. Step 1: Write the proportion equation
   9,991.16 : 13,787.55 = 5,514.90 : x
2. Step 2: Convert to fraction form
   9,991.16/13,787.55 = 5,514.90/x
3. Step 3: Cross multiply
   9,991.16x = 13,787.55 × 5,514.90
4. Step 4: Simplify right side
   9,991.16x = 76,036,959.50
5. Step 5: Solve for x
   x = 76,036,959.50/9,991.16
6. Step 6: Final answer
   x = 7,610.43