Finding the Fourth Proportional to 1,990.53, 2,747.39 and 1,290.69

Step by Step Solution

1. Step 1: Write the proportion equation
   1,990.53 : 2,747.39 = 1,290.69 : x
2. Step 2: Convert to fraction form
   1,990.53/2,747.39 = 1,290.69/x
3. Step 3: Cross multiply
   1,990.53x = 2,747.39 × 1,290.69
4. Step 4: Simplify right side
   1,990.53x = 3,546,022.35
5. Step 5: Solve for x
   x = 3,546,022.35/1,990.53
6. Step 6: Final answer
   x = 1,781.45