Finding the Fourth Proportional to 1,099.37, 1,656.79 and 989.82

Step by Step Solution

1. Step 1: Write the proportion equation
   1,099.37 : 1,656.79 = 989.82 : x
2. Step 2: Convert to fraction form
   1,099.37/1,656.79 = 989.82/x
3. Step 3: Cross multiply
   1,099.37x = 1,656.79 × 989.82
4. Step 4: Simplify right side
   1,099.37x = 1,639,921.40
5. Step 5: Solve for x
   x = 1,639,921.40/1,099.37
6. Step 6: Final answer
   x = 1,491.69