Finding the Fourth Proportional to 2,142.72, 3,214.56 and 988.56

Step by Step Solution

1. Step 1: Write the proportion equation
   2,142.72 : 3,214.56 = 988.56 : x
2. Step 2: Convert to fraction form
   2,142.72/3,214.56 = 988.56/x
3. Step 3: Cross multiply
   2,142.72x = 3,214.56 × 988.56
4. Step 4: Simplify right side
   2,142.72x = 3,177,785.43
5. Step 5: Solve for x
   x = 3,177,785.43/2,142.72
6. Step 6: Final answer
   x = 1,483.06