Finding the Fourth Proportional to 9,870.69, 13,619.84 and 5,891.57

Step by Step Solution

1. Step 1: Write the proportion equation
   9,870.69 : 13,619.84 = 5,891.57 : x
2. Step 2: Convert to fraction form
   9,870.69/13,619.84 = 5,891.57/x
3. Step 3: Cross multiply
   9,870.69x = 13,619.84 × 5,891.57
4. Step 4: Simplify right side
   9,870.69x = 80,242,143.19
5. Step 5: Solve for x
   x = 80,242,143.19/9,870.69
6. Step 6: Final answer
   x = 8,129.33