Finding the Fourth Proportional to 2,377.28, 3,564.66 and 990.89

Step by Step Solution

1. Step 1: Write the proportion equation
   2,377.28 : 3,564.66 = 990.89 : x
2. Step 2: Convert to fraction form
   2,377.28/3,564.66 = 990.89/x
3. Step 3: Cross multiply
   2,377.28x = 3,564.66 × 990.89
4. Step 4: Simplify right side
   2,377.28x = 3,532,185.95
5. Step 5: Solve for x
   x = 3,532,185.95/2,377.28
6. Step 6: Final answer
   x = 1,485.81