Finding the Fourth Proportional to 1,105.61, 1,656.91 and 611.28

Step by Step Solution

1. Step 1: Write the proportion equation
   1,105.61 : 1,656.91 = 611.28 : x
2. Step 2: Convert to fraction form
   1,105.61/1,656.91 = 611.28/x
3. Step 3: Cross multiply
   1,105.61x = 1,656.91 × 611.28
4. Step 4: Simplify right side
   1,105.61x = 1,012,840.26
5. Step 5: Solve for x
   x = 1,012,840.26/1,105.61
6. Step 6: Final answer
   x = 916.09