Finding the Fourth Proportional to 1,428.04, 1,969.82 and 1,261.72

Step by Step Solution

1. Step 1: Write the proportion equation
   1,428.04 : 1,969.82 = 1,261.72 : x
2. Step 2: Convert to fraction form
   1,428.04/1,969.82 = 1,261.72/x
3. Step 3: Cross multiply
   1,428.04x = 1,969.82 × 1,261.72
4. Step 4: Simplify right side
   1,428.04x = 2,485,361.29
5. Step 5: Solve for x
   x = 2,485,361.29/1,428.04
6. Step 6: Final answer
   x = 1,740.40