Finding the Fourth Proportional to 1,196.81, 1,651.50 and 665.65

Step by Step Solution

1. Step 1: Write the proportion equation
   1,196.81 : 1,651.50 = 665.65 : x
2. Step 2: Convert to fraction form
   1,196.81/1,651.50 = 665.65/x
3. Step 3: Cross multiply
   1,196.81x = 1,651.50 × 665.65
4. Step 4: Simplify right side
   1,196.81x = 1,099,320.98
5. Step 5: Solve for x
   x = 1,099,320.98/1,196.81
6. Step 6: Final answer
   x = 918.54