Finding the Fourth Proportional to 1,920.04, 2,650.72 and 1,212.80

Step by Step Solution

1. Step 1: Write the proportion equation
   1,920.04 : 2,650.72 = 1,212.80 : x
2. Step 2: Convert to fraction form
   1,920.04/2,650.72 = 1,212.80/x
3. Step 3: Cross multiply
   1,920.04x = 2,650.72 × 1,212.80
4. Step 4: Simplify right side
   1,920.04x = 3,214,793.22
5. Step 5: Solve for x
   x = 3,214,793.22/1,920.04
6. Step 6: Final answer
   x = 1,674.34