Finding the Fourth Proportional to 1,072.83, 1,609.83 and 423.57

Step by Step Solution

1. Step 1: Write the proportion equation
   1,072.83 : 1,609.83 = 423.57 : x
2. Step 2: Convert to fraction form
   1,072.83/1,609.83 = 423.57/x
3. Step 3: Cross multiply
   1,072.83x = 1,609.83 × 423.57
4. Step 4: Simplify right side
   1,072.83x = 681,875.69
5. Step 5: Solve for x
   x = 681,875.69/1,072.83
6. Step 6: Final answer
   x = 635.59