Finding the Fourth Proportional to 2,631.35, 3,946.86 and 987.76

Step by Step Solution

1. Step 1: Write the proportion equation
   2,631.35 : 3,946.86 = 987.76 : x
2. Step 2: Convert to fraction form
   2,631.35/3,946.86 = 987.76/x
3. Step 3: Cross multiply
   2,631.35x = 3,946.86 × 987.76
4. Step 4: Simplify right side
   2,631.35x = 3,898,550.43
5. Step 5: Solve for x
   x = 3,898,550.43/2,631.35
6. Step 6: Final answer
   x = 1,481.58