Finding the Fourth Proportional to 2,415.72, 3,333.72 and 1,311.72

Step by Step Solution

1. Step 1: Write the proportion equation
   2,415.72 : 3,333.72 = 1,311.72 : x
2. Step 2: Convert to fraction form
   2,415.72/3,333.72 = 1,311.72/x
3. Step 3: Cross multiply
   2,415.72x = 3,333.72 × 1,311.72
4. Step 4: Simplify right side
   2,415.72x = 4,372,907.20
5. Step 5: Solve for x
   x = 4,372,907.20/2,415.72
6. Step 6: Final answer
   x = 1,810.19