Finding the Fourth Proportional to 1,150.79, 1,726.88 and 420.42

Step by Step Solution

1. Step 1: Write the proportion equation
   1,150.79 : 1,726.88 = 420.42 : x
2. Step 2: Convert to fraction form
   1,150.79/1,726.88 = 420.42/x
3. Step 3: Cross multiply
   1,150.79x = 1,726.88 × 420.42
4. Step 4: Simplify right side
   1,150.79x = 726,012.79
5. Step 5: Solve for x
   x = 726,012.79/1,150.79
6. Step 6: Final answer
   x = 630.88