Finding the Fourth Proportional to 1,369.20, 1,890.30 and 1,085.34

Step by Step Solution

1. Step 1: Write the proportion equation
   1,369.20 : 1,890.30 = 1,085.34 : x
2. Step 2: Convert to fraction form
   1,369.20/1,890.30 = 1,085.34/x
3. Step 3: Cross multiply
   1,369.20x = 1,890.30 × 1,085.34
4. Step 4: Simplify right side
   1,369.20x = 2,051,618.20
5. Step 5: Solve for x
   x = 2,051,618.20/1,369.20
6. Step 6: Final answer
   x = 1,498.41