Finding the Fourth Proportional to 2,820.34, 3,891.69 and 1,640.50

Step by Step Solution

1. Step 1: Write the proportion equation
   2,820.34 : 3,891.69 = 1,640.50 : x
2. Step 2: Convert to fraction form
   2,820.34/3,891.69 = 1,640.50/x
3. Step 3: Cross multiply
   2,820.34x = 3,891.69 × 1,640.50
4. Step 4: Simplify right side
   2,820.34x = 6,384,317.45
5. Step 5: Solve for x
   x = 6,384,317.45/2,820.34
6. Step 6: Final answer
   x = 2,263.67