Finding the Fourth Proportional to 1,431.52, 1,975.20 and 841.72

Step by Step Solution

1. Step 1: Write the proportion equation
   1,431.52 : 1,975.20 = 841.72 : x
2. Step 2: Convert to fraction form
   1,431.52/1,975.20 = 841.72/x
3. Step 3: Cross multiply
   1,431.52x = 1,975.20 × 841.72
4. Step 4: Simplify right side
   1,431.52x = 1,662,565.34
5. Step 5: Solve for x
   x = 1,662,565.34/1,431.52
6. Step 6: Final answer
   x = 1,161.40