Finding the Fourth Proportional to 1,431.20, 1,975.18 and 801.72

Step by Step Solution

1. Step 1: Write the proportion equation
   1,431.20 : 1,975.18 = 801.72 : x
2. Step 2: Convert to fraction form
   1,431.20/1,975.18 = 801.72/x
3. Step 3: Cross multiply
   1,431.20x = 1,975.18 × 801.72
4. Step 4: Simplify right side
   1,431.20x = 1,583,537.37
5. Step 5: Solve for x
   x = 1,583,537.37/1,431.20
6. Step 6: Final answer
   x = 1,106.44