Finding the Fourth Proportional to 1,687.72, 2,329.23 and 979.42

Step by Step Solution

1. Step 1: Write the proportion equation
   1,687.72 : 2,329.23 = 979.42 : x
2. Step 2: Convert to fraction form
   1,687.72/2,329.23 = 979.42/x
3. Step 3: Cross multiply
   1,687.72x = 2,329.23 × 979.42
4. Step 4: Simplify right side
   1,687.72x = 2,281,301.23
5. Step 5: Solve for x
   x = 2,281,301.23/1,687.72
6. Step 6: Final answer
   x = 1,351.71