Finding the Fourth Proportional to 1,686.72, 2,526.52 and 862.48

Step by Step Solution

1. Step 1: Write the proportion equation
   1,686.72 : 2,526.52 = 862.48 : x
2. Step 2: Convert to fraction form
   1,686.72/2,526.52 = 862.48/x
3. Step 3: Cross multiply
   1,686.72x = 2,526.52 × 862.48
4. Step 4: Simplify right side
   1,686.72x = 2,179,072.97
5. Step 5: Solve for x
   x = 2,179,072.97/1,686.72
6. Step 6: Final answer
   x = 1,291.90