Finding the Fourth Proportional to 1,196.72, 1,651.38 and 665.60

Step by Step Solution

1. Step 1: Write the proportion equation
   1,196.72 : 1,651.38 = 665.60 : x
2. Step 2: Convert to fraction form
   1,196.72/1,651.38 = 665.60/x
3. Step 3: Cross multiply
   1,196.72x = 1,651.38 × 665.60
4. Step 4: Simplify right side
   1,196.72x = 1,099,165.20
5. Step 5: Solve for x
   x = 1,099,165.20/1,196.72
6. Step 6: Final answer
   x = 918.48