Finding the Fourth Proportional to 2,164.32, 2,986.47 and 1,279.80

Step by Step Solution

1. Step 1: Write the proportion equation
   2,164.32 : 2,986.47 = 1,279.80 : x
2. Step 2: Convert to fraction form
   2,164.32/2,986.47 = 1,279.80/x
3. Step 3: Cross multiply
   2,164.32x = 2,986.47 × 1,279.80
4. Step 4: Simplify right side
   2,164.32x = 3,822,084.31
5. Step 5: Solve for x
   x = 3,822,084.31/2,164.32
6. Step 6: Final answer
   x = 1,765.95