Finding the Fourth Proportional to 1,181.14, 1,770.56 and 661.39

Step by Step Solution

1. Step 1: Write the proportion equation
   1,181.14 : 1,770.56 = 661.39 : x
2. Step 2: Convert to fraction form
   1,181.14/1,770.56 = 661.39/x
3. Step 3: Cross multiply
   1,181.14x = 1,770.56 × 661.39
4. Step 4: Simplify right side
   1,181.14x = 1,171,018.52
5. Step 5: Solve for x
   x = 1,171,018.52/1,181.14
6. Step 6: Final answer
   x = 991.43