Finding the Fourth Proportional to 2,279.72, 3,417.45 and 1,238.20

Step by Step Solution

1. Step 1: Write the proportion equation
   2,279.72 : 3,417.45 = 1,238.20 : x
2. Step 2: Convert to fraction form
   2,279.72/3,417.45 = 1,238.20/x
3. Step 3: Cross multiply
   2,279.72x = 3,417.45 × 1,238.20
4. Step 4: Simplify right side
   2,279.72x = 4,231,486.59
5. Step 5: Solve for x
   x = 4,231,486.59/2,279.72
6. Step 6: Final answer
   x = 1,856.14