Finding the Fourth Proportional to 1,085.15, 1,628.02 and 436.34

Step by Step Solution

1. Step 1: Write the proportion equation
   1,085.15 : 1,628.02 = 436.34 : x
2. Step 2: Convert to fraction form
   1,085.15/1,628.02 = 436.34/x
3. Step 3: Cross multiply
   1,085.15x = 1,628.02 × 436.34
4. Step 4: Simplify right side
   1,085.15x = 710,370.25
5. Step 5: Solve for x
   x = 710,370.25/1,085.15
6. Step 6: Final answer
   x = 654.63