Finding the Fourth Proportional to 1,377.59, 1,900.80 and 853.38

Step by Step Solution

1. Step 1: Write the proportion equation
   1,377.59 : 1,900.80 = 853.38 : x
2. Step 2: Convert to fraction form
   1,377.59/1,900.80 = 853.38/x
3. Step 3: Cross multiply
   1,377.59x = 1,900.80 × 853.38
4. Step 4: Simplify right side
   1,377.59x = 1,622,104.70
5. Step 5: Solve for x
   x = 1,622,104.70/1,377.59
6. Step 6: Final answer
   x = 1,177.50