Finding the Fourth Proportional to 9,870.40, 13,621.34 and 5,394.42

Step by Step Solution

1. Step 1: Write the proportion equation
   9,870.40 : 13,621.34 = 5,394.42 : x
2. Step 2: Convert to fraction form
   9,870.40/13,621.34 = 5,394.42/x
3. Step 3: Cross multiply
   9,870.40x = 13,621.34 × 5,394.42
4. Step 4: Simplify right side
   9,870.40x = 73,479,262.98
5. Step 5: Solve for x
   x = 73,479,262.98/9,870.40
6. Step 6: Final answer
   x = 7,444.41