Finding the Fourth Proportional to 9,870.39, 13,621.16 and 5,394.20

Step by Step Solution

1. Step 1: Write the proportion equation
   9,870.39 : 13,621.16 = 5,394.20 : x
2. Step 2: Convert to fraction form
   9,870.39/13,621.16 = 5,394.20/x
3. Step 3: Cross multiply
   9,870.39x = 13,621.16 × 5,394.20
4. Step 4: Simplify right side
   9,870.39x = 73,475,206.65
5. Step 5: Solve for x
   x = 73,475,206.65/9,870.39
6. Step 6: Final answer
   x = 7,444.00