Finding the Fourth Proportional to 2,557.51, 3,529.40 and 1,438.42

Step by Step Solution

1. Step 1: Write the proportion equation
   2,557.51 : 3,529.40 = 1,438.42 : x
2. Step 2: Convert to fraction form
   2,557.51/3,529.40 = 1,438.42/x
3. Step 3: Cross multiply
   2,557.51x = 3,529.40 × 1,438.42
4. Step 4: Simplify right side
   2,557.51x = 5,076,759.55
5. Step 5: Solve for x
   x = 5,076,759.55/2,557.51
6. Step 6: Final answer
   x = 1,985.04