Finding the Fourth Proportional to 1,776.38, 2,451.42 and 990.50

Step by Step Solution

1. Step 1: Write the proportion equation
   1,776.38 : 2,451.42 = 990.50 : x
2. Step 2: Convert to fraction form
   1,776.38/2,451.42 = 990.50/x
3. Step 3: Cross multiply
   1,776.38x = 2,451.42 × 990.50
4. Step 4: Simplify right side
   1,776.38x = 2,428,119.25
5. Step 5: Solve for x
   x = 2,428,119.25/1,776.38
6. Step 6: Final answer
   x = 1,366.90