Finding the Fourth Proportional to 1,173.06, 1,618.82 and 641.94

Step by Step Solution

1. Step 1: Write the proportion equation
   1,173.06 : 1,618.82 = 641.94 : x
2. Step 2: Convert to fraction form
   1,173.06/1,618.82 = 641.94/x
3. Step 3: Cross multiply
   1,173.06x = 1,618.82 × 641.94
4. Step 4: Simplify right side
   1,173.06x = 1,039,182.10
5. Step 5: Solve for x
   x = 1,039,182.10/1,173.06
6. Step 6: Final answer
   x = 885.87