Finding the Fourth Proportional to 1,377.11, 1,900.12 and 817.50

Step by Step Solution

1. Step 1: Write the proportion equation
   1,377.11 : 1,900.12 = 817.50 : x
2. Step 2: Convert to fraction form
   1,377.11/1,900.12 = 817.50/x
3. Step 3: Cross multiply
   1,377.11x = 1,900.12 × 817.50
4. Step 4: Simplify right side
   1,377.11x = 1,553,348.10
5. Step 5: Solve for x
   x = 1,553,348.10/1,377.11
6. Step 6: Final answer
   x = 1,127.98