Finding the Fourth Proportional to 2,086.87, 3,130.37 and 990.67

Step by Step Solution

1. Step 1: Write the proportion equation
   2,086.87 : 3,130.37 = 990.67 : x
2. Step 2: Convert to fraction form
   2,086.87/3,130.37 = 990.67/x
3. Step 3: Cross multiply
   2,086.87x = 3,130.37 × 990.67
4. Step 4: Simplify right side
   2,086.87x = 3,101,143.04
5. Step 5: Solve for x
   x = 3,101,143.04/2,086.87
6. Step 6: Final answer
   x = 1,486.03