Finding the Fourth Proportional to 9,990.31, 13,786.44 and 5,513.80

Step by Step Solution

1. Step 1: Write the proportion equation
   9,990.31 : 13,786.44 = 5,513.80 : x
2. Step 2: Convert to fraction form
   9,990.31/13,786.44 = 5,513.80/x
3. Step 3: Cross multiply
   9,990.31x = 13,786.44 × 5,513.80
4. Step 4: Simplify right side
   9,990.31x = 76,015,672.87
5. Step 5: Solve for x
   x = 76,015,672.87/9,990.31
6. Step 6: Final answer
   x = 7,608.94