Finding the Fourth Proportional to 981.79, 1,471.89 and 672.88

Step by Step Solution

1. Step 1: Write the proportion equation
   981.79 : 1,471.89 = 672.88 : x
2. Step 2: Convert to fraction form
   981.79/1,471.89 = 672.88/x
3. Step 3: Cross multiply
   981.79x = 1,471.89 × 672.88
4. Step 4: Simplify right side
   981.79x = 990,405.34
5. Step 5: Solve for x
   x = 990,405.34/981.79
6. Step 6: Final answer
   x = 1,008.78