Finding the Fourth Proportional to 2,189.67, 3,285.72 and 1,640.22

Step by Step Solution

1. Step 1: Write the proportion equation
   2,189.67 : 3,285.72 = 1,640.22 : x
2. Step 2: Convert to fraction form
   2,189.67/3,285.72 = 1,640.22/x
3. Step 3: Cross multiply
   2,189.67x = 3,285.72 × 1,640.22
4. Step 4: Simplify right side
   2,189.67x = 5,389,303.66
5. Step 5: Solve for x
   x = 5,389,303.66/2,189.67
6. Step 6: Final answer
   x = 2,461.24