Finding the Fourth Proportional to 1,091.56, 1,506.87 and 698.81

Step by Step Solution

1. Step 1: Write the proportion equation
   1,091.56 : 1,506.87 = 698.81 : x
2. Step 2: Convert to fraction form
   1,091.56/1,506.87 = 698.81/x
3. Step 3: Cross multiply
   1,091.56x = 1,506.87 × 698.81
4. Step 4: Simplify right side
   1,091.56x = 1,053,012.33
5. Step 5: Solve for x
   x = 1,053,012.33/1,091.56
6. Step 6: Final answer
   x = 964.69