Finding the Fourth Proportional to 9,870.94, 13,622.78 and 5,621.07

Step by Step Solution

1. Step 1: Write the proportion equation
   9,870.94 : 13,622.78 = 5,621.07 : x
2. Step 2: Convert to fraction form
   9,870.94/13,622.78 = 5,621.07/x
3. Step 3: Cross multiply
   9,870.94x = 13,622.78 × 5,621.07
4. Step 4: Simplify right side
   9,870.94x = 76,574,626.80
5. Step 5: Solve for x
   x = 76,574,626.80/9,870.94
6. Step 6: Final answer
   x = 7,757.58