Finding the Fourth Proportional to 2,085.40, 3,120.78 and 1,648

Step by Step Solution

1. Step 1: Write the proportion equation
   2,085.40 : 3,120.78 = 1,648 : x
2. Step 2: Convert to fraction form
   2,085.40/3,120.78 = 1,648/x
3. Step 3: Cross multiply
   2,085.40x = 3,120.78 × 1,648
4. Step 4: Simplify right side
   2,085.40x = 5,143,045.44
5. Step 5: Solve for x
   x = 5,143,045.44/2,085.40
6. Step 6: Final answer
   x = 2,466.22