Finding the Fourth Proportional to 1,162.28, 1,603.86 and 664.90

Step by Step Solution

1. Step 1: Write the proportion equation
   1,162.28 : 1,603.86 = 664.90 : x
2. Step 2: Convert to fraction form
   1,162.28/1,603.86 = 664.90/x
3. Step 3: Cross multiply
   1,162.28x = 1,603.86 × 664.90
4. Step 4: Simplify right side
   1,162.28x = 1,066,406.51
5. Step 5: Solve for x
   x = 1,066,406.51/1,162.28
6. Step 6: Final answer
   x = 917.51