Finding the Fourth Proportional to 1,290.23, 1,775.89 and 1,078.01

Step by Step Solution

1. Step 1: Write the proportion equation
   1,290.23 : 1,775.89 = 1,078.01 : x
2. Step 2: Convert to fraction form
   1,290.23/1,775.89 = 1,078.01/x
3. Step 3: Cross multiply
   1,290.23x = 1,775.89 × 1,078.01
4. Step 4: Simplify right side
   1,290.23x = 1,914,426.31
5. Step 5: Solve for x
   x = 1,914,426.31/1,290.23
6. Step 6: Final answer
   x = 1,483.79