Finding the Fourth Proportional to 1,165.09, 1,607.82 and 641.15

Step by Step Solution

1. Step 1: Write the proportion equation
   1,165.09 : 1,607.82 = 641.15 : x
2. Step 2: Convert to fraction form
   1,165.09/1,607.82 = 641.15/x
3. Step 3: Cross multiply
   1,165.09x = 1,607.82 × 641.15
4. Step 4: Simplify right side
   1,165.09x = 1,030,853.79
5. Step 5: Solve for x
   x = 1,030,853.79/1,165.09
6. Step 6: Final answer
   x = 884.79