Finding the Fourth Proportional to 1,323.78, 1,984.59 and 890.70

Step by Step Solution

1. Step 1: Write the proportion equation
   1,323.78 : 1,984.59 = 890.70 : x
2. Step 2: Convert to fraction form
   1,323.78/1,984.59 = 890.70/x
3. Step 3: Cross multiply
   1,323.78x = 1,984.59 × 890.70
4. Step 4: Simplify right side
   1,323.78x = 1,767,674.31
5. Step 5: Solve for x
   x = 1,767,674.31/1,323.78
6. Step 6: Final answer
   x = 1,335.32