Finding the Fourth Proportional to 3,776.72, 5,664.32 and 1,311.65

Step by Step Solution

1. Step 1: Write the proportion equation
   3,776.72 : 5,664.32 = 1,311.65 : x
2. Step 2: Convert to fraction form
   3,776.72/5,664.32 = 1,311.65/x
3. Step 3: Cross multiply
   3,776.72x = 5,664.32 × 1,311.65
4. Step 4: Simplify right side
   3,776.72x = 7,429,570.45
5. Step 5: Solve for x
   x = 7,429,570.45/3,776.72
6. Step 6: Final answer
   x = 1,967.20