Finding the Fourth Proportional to 1,396.59, 2,091.69 and 666.68

Step by Step Solution

1. Step 1: Write the proportion equation
   1,396.59 : 2,091.69 = 666.68 : x
2. Step 2: Convert to fraction form
   1,396.59/2,091.69 = 666.68/x
3. Step 3: Cross multiply
   1,396.59x = 2,091.69 × 666.68
4. Step 4: Simplify right side
   1,396.59x = 1,394,484.33
5. Step 5: Solve for x
   x = 1,394,484.33/1,396.59
6. Step 6: Final answer
   x = 998.49