Finding the Fourth Proportional to 2,517.60, 3,474.36 and 1,398.72

Step by Step Solution

1. Step 1: Write the proportion equation
   2,517.60 : 3,474.36 = 1,398.72 : x
2. Step 2: Convert to fraction form
   2,517.60/3,474.36 = 1,398.72/x
3. Step 3: Cross multiply
   2,517.60x = 3,474.36 × 1,398.72
4. Step 4: Simplify right side
   2,517.60x = 4,859,656.82
5. Step 5: Solve for x
   x = 4,859,656.82/2,517.60
6. Step 6: Final answer
   x = 1,930.27