Finding the Fourth Proportional to 1,171.82, 1,617.02 and 647.78

Step by Step Solution

1. Step 1: Write the proportion equation
   1,171.82 : 1,617.02 = 647.78 : x
2. Step 2: Convert to fraction form
   1,171.82/1,617.02 = 647.78/x
3. Step 3: Cross multiply
   1,171.82x = 1,617.02 × 647.78
4. Step 4: Simplify right side
   1,171.82x = 1,047,473.22
5. Step 5: Solve for x
   x = 1,047,473.22/1,171.82
6. Step 6: Final answer
   x = 893.89