Finding the Fourth Proportional to 1,109.78, 1,531.42 and 612.32

Step by Step Solution

1. Step 1: Write the proportion equation
   1,109.78 : 1,531.42 = 612.32 : x
2. Step 2: Convert to fraction form
   1,109.78/1,531.42 = 612.32/x
3. Step 3: Cross multiply
   1,109.78x = 1,531.42 × 612.32
4. Step 4: Simplify right side
   1,109.78x = 937,713.35
5. Step 5: Solve for x
   x = 937,713.35/1,109.78
6. Step 6: Final answer
   x = 844.95