Finding the Fourth Proportional to 1,028.68, 1,419.86 and 661.32

Step by Step Solution

1. Step 1: Write the proportion equation
   1,028.68 : 1,419.86 = 661.32 : x
2. Step 2: Convert to fraction form
   1,028.68/1,419.86 = 661.32/x
3. Step 3: Cross multiply
   1,028.68x = 1,419.86 × 661.32
4. Step 4: Simplify right side
   1,028.68x = 938,981.82
5. Step 5: Solve for x
   x = 938,981.82/1,028.68
6. Step 6: Final answer
   x = 912.80