Finding the Fourth Proportional to 1,164.79, 1,607.42 and 640.82

Step by Step Solution

1. Step 1: Write the proportion equation
   1,164.79 : 1,607.42 = 640.82 : x
2. Step 2: Convert to fraction form
   1,164.79/1,607.42 = 640.82/x
3. Step 3: Cross multiply
   1,164.79x = 1,607.42 × 640.82
4. Step 4: Simplify right side
   1,164.79x = 1,030,066.88
5. Step 5: Solve for x
   x = 1,030,066.88/1,164.79
6. Step 6: Final answer
   x = 884.34