Finding the Fourth Proportional to 1,231.57, 1,699.56 and 672.05

Step by Step Solution

1. Step 1: Write the proportion equation
   1,231.57 : 1,699.56 = 672.05 : x
2. Step 2: Convert to fraction form
   1,231.57/1,699.56 = 672.05/x
3. Step 3: Cross multiply
   1,231.57x = 1,699.56 × 672.05
4. Step 4: Simplify right side
   1,231.57x = 1,142,189.30
5. Step 5: Solve for x
   x = 1,142,189.30/1,231.57
6. Step 6: Final answer
   x = 927.43