Finding the Fourth Proportional to 1,431.47, 2,147.89 and 782.18

Step by Step Solution

1. Step 1: Write the proportion equation
   1,431.47 : 2,147.89 = 782.18 : x
2. Step 2: Convert to fraction form
   1,431.47/2,147.89 = 782.18/x
3. Step 3: Cross multiply
   1,431.47x = 2,147.89 × 782.18
4. Step 4: Simplify right side
   1,431.47x = 1,680,040.01
5. Step 5: Solve for x
   x = 1,680,040.01/1,431.47
6. Step 6: Final answer
   x = 1,173.65