Finding the Fourth Proportional to 1,427.78, 1,969.17 and 1,420.49

Step by Step Solution

1. Step 1: Write the proportion equation
   1,427.78 : 1,969.17 = 1,420.49 : x
2. Step 2: Convert to fraction form
   1,427.78/1,969.17 = 1,420.49/x
3. Step 3: Cross multiply
   1,427.78x = 1,969.17 × 1,420.49
4. Step 4: Simplify right side
   1,427.78x = 2,797,186.29
5. Step 5: Solve for x
   x = 2,797,186.29/1,427.78
6. Step 6: Final answer
   x = 1,959.12