Finding the Fourth Proportional to 1,423.37, 2,128.68 and 928.46

Step by Step Solution

1. Step 1: Write the proportion equation
   1,423.37 : 2,128.68 = 928.46 : x
2. Step 2: Convert to fraction form
   1,423.37/2,128.68 = 928.46/x
3. Step 3: Cross multiply
   1,423.37x = 2,128.68 × 928.46
4. Step 4: Simplify right side
   1,423.37x = 1,976,399.55
5. Step 5: Solve for x
   x = 1,976,399.55/1,423.37
6. Step 6: Final answer
   x = 1,388.53