Finding the Fourth Proportional to 1,118.55, 1,543.55 and 646.37

Step by Step Solution

1. Step 1: Write the proportion equation
   1,118.55 : 1,543.55 = 646.37 : x
2. Step 2: Convert to fraction form
   1,118.55/1,543.55 = 646.37/x
3. Step 3: Cross multiply
   1,118.55x = 1,543.55 × 646.37
4. Step 4: Simplify right side
   1,118.55x = 997,709.89
5. Step 5: Solve for x
   x = 997,709.89/1,118.55
6. Step 6: Final answer
   x = 891.97