Finding the Fourth Proportional to 2,145.65, 2,961.72 and 1,261.71

Step by Step Solution

1. Step 1: Write the proportion equation
   2,145.65 : 2,961.72 = 1,261.71 : x
2. Step 2: Convert to fraction form
   2,145.65/2,961.72 = 1,261.71/x
3. Step 3: Cross multiply
   2,145.65x = 2,961.72 × 1,261.71
4. Step 4: Simplify right side
   2,145.65x = 3,736,831.74
5. Step 5: Solve for x
   x = 3,736,831.74/2,145.65
6. Step 6: Final answer
   x = 1,741.59