Finding the Fourth Proportional to 1,212.80, 1,672.72 and 1,045.04

Step by Step Solution

1. Step 1: Write the proportion equation
   1,212.80 : 1,672.72 = 1,045.04 : x
2. Step 2: Convert to fraction form
   1,212.80/1,672.72 = 1,045.04/x
3. Step 3: Cross multiply
   1,212.80x = 1,672.72 × 1,045.04
4. Step 4: Simplify right side
   1,212.80x = 1,748,059.31
5. Step 5: Solve for x
   x = 1,748,059.31/1,212.80
6. Step 6: Final answer
   x = 1,441.34