Finding the Fourth Proportional to 1,372.12, 1,893.12 and 1,057.72

Step by Step Solution

1. Step 1: Write the proportion equation
   1,372.12 : 1,893.12 = 1,057.72 : x
2. Step 2: Convert to fraction form
   1,372.12/1,893.12 = 1,057.72/x
3. Step 3: Cross multiply
   1,372.12x = 1,893.12 × 1,057.72
4. Step 4: Simplify right side
   1,372.12x = 2,002,390.89
5. Step 5: Solve for x
   x = 2,002,390.89/1,372.12
6. Step 6: Final answer
   x = 1,459.34