Finding the Fourth Proportional to 1,528.90, 2,106.85 and 1,085.56

Step by Step Solution

1. Step 1: Write the proportion equation
   1,528.90 : 2,106.85 = 1,085.56 : x
2. Step 2: Convert to fraction form
   1,528.90/2,106.85 = 1,085.56/x
3. Step 3: Cross multiply
   1,528.90x = 2,106.85 × 1,085.56
4. Step 4: Simplify right side
   1,528.90x = 2,287,104.10
5. Step 5: Solve for x
   x = 2,287,104.10/1,528.90
6. Step 6: Final answer
   x = 1,495.92