Finding the Fourth Proportional to 9,986.50, 13,781.37 and 5,570.50

Step by Step Solution

1. Step 1: Write the proportion equation
   9,986.50 : 13,781.37 = 5,570.50 : x
2. Step 2: Convert to fraction form
   9,986.50/13,781.37 = 5,570.50/x
3. Step 3: Cross multiply
   9,986.50x = 13,781.37 × 5,570.50
4. Step 4: Simplify right side
   9,986.50x = 76,769,121.59
5. Step 5: Solve for x
   x = 76,769,121.59/9,986.50
6. Step 6: Final answer
   x = 7,687.29