Finding the Fourth Proportional to 1,109.88, 1,531.57 and 612.42

Step by Step Solution

1. Step 1: Write the proportion equation
   1,109.88 : 1,531.57 = 612.42 : x
2. Step 2: Convert to fraction form
   1,109.88/1,531.57 = 612.42/x
3. Step 3: Cross multiply
   1,109.88x = 1,531.57 × 612.42
4. Step 4: Simplify right side
   1,109.88x = 937,964.10
5. Step 5: Solve for x
   x = 937,964.10/1,109.88
6. Step 6: Final answer
   x = 845.10