Finding the Fourth Proportional to 1,116.23, 1,673.89 and 422.78

Step by Step Solution

1. Step 1: Write the proportion equation
   1,116.23 : 1,673.89 = 422.78 : x
2. Step 2: Convert to fraction form
   1,116.23/1,673.89 = 422.78/x
3. Step 3: Cross multiply
   1,116.23x = 1,673.89 × 422.78
4. Step 4: Simplify right side
   1,116.23x = 707,677.79
5. Step 5: Solve for x
   x = 707,677.79/1,116.23
6. Step 6: Final answer
   x = 633.99