Finding the Fourth Proportional to 1,398.02, 1,928.72 and 866.72

Step by Step Solution

1. Step 1: Write the proportion equation
   1,398.02 : 1,928.72 = 866.72 : x
2. Step 2: Convert to fraction form
   1,398.02/1,928.72 = 866.72/x
3. Step 3: Cross multiply
   1,398.02x = 1,928.72 × 866.72
4. Step 4: Simplify right side
   1,398.02x = 1,671,646.22
5. Step 5: Solve for x
   x = 1,671,646.22/1,398.02
6. Step 6: Final answer
   x = 1,195.73