Finding the Fourth Proportional to 1,095.34, 1,639.76 and 661.18

Step by Step Solution

1. Step 1: Write the proportion equation
   1,095.34 : 1,639.76 = 661.18 : x
2. Step 2: Convert to fraction form
   1,095.34/1,639.76 = 661.18/x
3. Step 3: Cross multiply
   1,095.34x = 1,639.76 × 661.18
4. Step 4: Simplify right side
   1,095.34x = 1,084,176.52
5. Step 5: Solve for x
   x = 1,084,176.52/1,095.34
6. Step 6: Final answer
   x = 989.81