Finding the Fourth Proportional to 1,422.46, 2,128.29 and 1,278.58

Step by Step Solution

1. Step 1: Write the proportion equation
   1,422.46 : 2,128.29 = 1,278.58 : x
2. Step 2: Convert to fraction form
   1,422.46/2,128.29 = 1,278.58/x
3. Step 3: Cross multiply
   1,422.46x = 2,128.29 × 1,278.58
4. Step 4: Simplify right side
   1,422.46x = 2,721,189.03
5. Step 5: Solve for x
   x = 2,721,189.03/1,422.46
6. Step 6: Final answer
   x = 1,913.02