Finding the Fourth Proportional to 3,621.55, 5,431.89 and 989.25

Step by Step Solution

1. Step 1: Write the proportion equation
   3,621.55 : 5,431.89 = 989.25 : x
2. Step 2: Convert to fraction form
   3,621.55/5,431.89 = 989.25/x
3. Step 3: Cross multiply
   3,621.55x = 5,431.89 × 989.25
4. Step 4: Simplify right side
   3,621.55x = 5,373,511.08
5. Step 5: Solve for x
   x = 5,373,511.08/3,621.55
6. Step 6: Final answer
   x = 1,483.76