Finding the Fourth Proportional to 1,162.51, 1,603.89 and 665.10

Step by Step Solution

1. Step 1: Write the proportion equation
   1,162.51 : 1,603.89 = 665.10 : x
2. Step 2: Convert to fraction form
   1,162.51/1,603.89 = 665.10/x
3. Step 3: Cross multiply
   1,162.51x = 1,603.89 × 665.10
4. Step 4: Simplify right side
   1,162.51x = 1,066,747.24
5. Step 5: Solve for x
   x = 1,066,747.24/1,162.51
6. Step 6: Final answer
   x = 917.63