Finding the Fourth Proportional to 3,643.35, 5,421.42 and 3,631.06

Step by Step Solution

1. Step 1: Write the proportion equation
   3,643.35 : 5,421.42 = 3,631.06 : x
2. Step 2: Convert to fraction form
   3,643.35/5,421.42 = 3,631.06/x
3. Step 3: Cross multiply
   3,643.35x = 5,421.42 × 3,631.06
4. Step 4: Simplify right side
   3,643.35x = 19,685,501.31
5. Step 5: Solve for x
   x = 19,685,501.31/3,643.35
6. Step 6: Final answer
   x = 5,403.13