Finding the Fourth Proportional to 2,279.81, 3,145.75 and 1,271.30

Step by Step Solution

1. Step 1: Write the proportion equation
   2,279.81 : 3,145.75 = 1,271.30 : x
2. Step 2: Convert to fraction form
   2,279.81/3,145.75 = 1,271.30/x
3. Step 3: Cross multiply
   2,279.81x = 3,145.75 × 1,271.30
4. Step 4: Simplify right side
   2,279.81x = 3,999,191.98
5. Step 5: Solve for x
   x = 3,999,191.98/2,279.81
6. Step 6: Final answer
   x = 1,754.18