Finding the Fourth Proportional to 2,557.31, 3,528.48 and 1,438.03

Step by Step Solution

1. Step 1: Write the proportion equation
   2,557.31 : 3,528.48 = 1,438.03 : x
2. Step 2: Convert to fraction form
   2,557.31/3,528.48 = 1,438.03/x
3. Step 3: Cross multiply
   2,557.31x = 3,528.48 × 1,438.03
4. Step 4: Simplify right side
   2,557.31x = 5,074,051.27
5. Step 5: Solve for x
   x = 5,074,051.27/2,557.31
6. Step 6: Final answer
   x = 1,984.13