Finding the Fourth Proportional to 1,208.63, 1,667.78 and 684.63

Step by Step Solution

1. Step 1: Write the proportion equation
   1,208.63 : 1,667.78 = 684.63 : x
2. Step 2: Convert to fraction form
   1,208.63/1,667.78 = 684.63/x
3. Step 3: Cross multiply
   1,208.63x = 1,667.78 × 684.63
4. Step 4: Simplify right side
   1,208.63x = 1,141,812.22
5. Step 5: Solve for x
   x = 1,141,812.22/1,208.63
6. Step 6: Final answer
   x = 944.72