Finding the Fourth Proportional to 2,145.58, 2,961.28 and 1,261.43

Step by Step Solution

1. Step 1: Write the proportion equation
   2,145.58 : 2,961.28 = 1,261.43 : x
2. Step 2: Convert to fraction form
   2,145.58/2,961.28 = 1,261.43/x
3. Step 3: Cross multiply
   2,145.58x = 2,961.28 × 1,261.43
4. Step 4: Simplify right side
   2,145.58x = 3,735,432.62
5. Step 5: Solve for x
   x = 3,735,432.62/2,145.58
6. Step 6: Final answer
   x = 1,740.99