Finding the Fourth Proportional to 1,399.55, 2,099.93 and 669.06

Step by Step Solution

1. Step 1: Write the proportion equation
   1,399.55 : 2,099.93 = 669.06 : x
2. Step 2: Convert to fraction form
   1,399.55/2,099.93 = 669.06/x
3. Step 3: Cross multiply
   1,399.55x = 2,099.93 × 669.06
4. Step 4: Simplify right side
   1,399.55x = 1,404,975.82
5. Step 5: Solve for x
   x = 1,404,975.82/1,399.55
6. Step 6: Final answer
   x = 1,003.88