Finding the Fourth Proportional to 1,109.89, 1,531.65 and 612.53

Step by Step Solution

1. Step 1: Write the proportion equation
   1,109.89 : 1,531.65 = 612.53 : x
2. Step 2: Convert to fraction form
   1,109.89/1,531.65 = 612.53/x
3. Step 3: Cross multiply
   1,109.89x = 1,531.65 × 612.53
4. Step 4: Simplify right side
   1,109.89x = 938,181.96
5. Step 5: Solve for x
   x = 938,181.96/1,109.89
6. Step 6: Final answer
   x = 845.29