Finding the Fourth Proportional to 2,557.48, 3,529.34 and 1,438.47

Step by Step Solution

1. Step 1: Write the proportion equation
   2,557.48 : 3,529.34 = 1,438.47 : x
2. Step 2: Convert to fraction form
   2,557.48/3,529.34 = 1,438.47/x
3. Step 3: Cross multiply
   2,557.48x = 3,529.34 × 1,438.47
4. Step 4: Simplify right side
   2,557.48x = 5,076,849.71
5. Step 5: Solve for x
   x = 5,076,849.71/2,557.48
6. Step 6: Final answer
   x = 1,985.10