Finding the Fourth Proportional to 1,158.72, 1,736.52 and 427.59

Step by Step Solution

1. Step 1: Write the proportion equation
   1,158.72 : 1,736.52 = 427.59 : x
2. Step 2: Convert to fraction form
   1,158.72/1,736.52 = 427.59/x
3. Step 3: Cross multiply
   1,158.72x = 1,736.52 × 427.59
4. Step 4: Simplify right side
   1,158.72x = 742,518.59
5. Step 5: Solve for x
   x = 742,518.59/1,158.72
6. Step 6: Final answer
   x = 640.81