Finding the Fourth Proportional to 1,166.81, 1,610.16 and 642.83

Step by Step Solution

1. Step 1: Write the proportion equation
   1,166.81 : 1,610.16 = 642.83 : x
2. Step 2: Convert to fraction form
   1,166.81/1,610.16 = 642.83/x
3. Step 3: Cross multiply
   1,166.81x = 1,610.16 × 642.83
4. Step 4: Simplify right side
   1,166.81x = 1,035,051.10
5. Step 5: Solve for x
   x = 1,035,051.10/1,166.81
6. Step 6: Final answer
   x = 887.08