Finding the Fourth Proportional to 2,520.71, 3,480.65 and 1,638.02

Step by Step Solution

1. Step 1: Write the proportion equation
   2,520.71 : 3,480.65 = 1,638.02 : x
2. Step 2: Convert to fraction form
   2,520.71/3,480.65 = 1,638.02/x
3. Step 3: Cross multiply
   2,520.71x = 3,480.65 × 1,638.02
4. Step 4: Simplify right side
   2,520.71x = 5,701,348.72
5. Step 5: Solve for x
   x = 5,701,348.72/2,520.71
6. Step 6: Final answer
   x = 2,261.81