Finding the Fourth Proportional to 1,091.98, 1,506.61 and 986.73

Step by Step Solution

1. Step 1: Write the proportion equation
   1,091.98 : 1,506.61 = 986.73 : x
2. Step 2: Convert to fraction form
   1,091.98/1,506.61 = 986.73/x
3. Step 3: Cross multiply
   1,091.98x = 1,506.61 × 986.73
4. Step 4: Simplify right side
   1,091.98x = 1,486,614.23
5. Step 5: Solve for x
   x = 1,486,614.23/1,091.98
6. Step 6: Final answer
   x = 1,361.39