Finding the Fourth Proportional to 1,091.61, 1,625.06 and 1,085.12

Step by Step Solution

1. Step 1: Write the proportion equation
   1,091.61 : 1,625.06 = 1,085.12 : x
2. Step 2: Convert to fraction form
   1,091.61/1,625.06 = 1,085.12/x
3. Step 3: Cross multiply
   1,091.61x = 1,625.06 × 1,085.12
4. Step 4: Simplify right side
   1,091.61x = 1,763,383.76
5. Step 5: Solve for x
   x = 1,763,383.76/1,091.61
6. Step 6: Final answer
   x = 1,615.40