Finding the Fourth Proportional to 1,442.62, 1,990.70 and 853.05

Step by Step Solution

1. Step 1: Write the proportion equation
   1,442.62 : 1,990.70 = 853.05 : x
2. Step 2: Convert to fraction form
   1,442.62/1,990.70 = 853.05/x
3. Step 3: Cross multiply
   1,442.62x = 1,990.70 × 853.05
4. Step 4: Simplify right side
   1,442.62x = 1,698,166.64
5. Step 5: Solve for x
   x = 1,698,166.64/1,442.62
6. Step 6: Final answer
   x = 1,177.14