Finding the Fourth Proportional to 1,640.46, 2,456.10 and 1,279.48

Step by Step Solution

1. Step 1: Write the proportion equation
   1,640.46 : 2,456.10 = 1,279.48 : x
2. Step 2: Convert to fraction form
   1,640.46/2,456.10 = 1,279.48/x
3. Step 3: Cross multiply
   1,640.46x = 2,456.10 × 1,279.48
4. Step 4: Simplify right side
   1,640.46x = 3,142,530.83
5. Step 5: Solve for x
   x = 3,142,530.83/1,640.46
6. Step 6: Final answer
   x = 1,915.64