Finding the Fourth Proportional to 1,811.68, 2,713.20 and 988.72

Step by Step Solution

1. Step 1: Write the proportion equation
   1,811.68 : 2,713.20 = 988.72 : x
2. Step 2: Convert to fraction form
   1,811.68/2,713.20 = 988.72/x
3. Step 3: Cross multiply
   1,811.68x = 2,713.20 × 988.72
4. Step 4: Simplify right side
   1,811.68x = 2,682,595.10
5. Step 5: Solve for x
   x = 2,682,595.10/1,811.68
6. Step 6: Final answer
   x = 1,480.72