Finding the Fourth Proportional to 1,408.72, 2,113.84 and 668.16

Step by Step Solution

1. Step 1: Write the proportion equation
   1,408.72 : 2,113.84 = 668.16 : x
2. Step 2: Convert to fraction form
   1,408.72/2,113.84 = 668.16/x
3. Step 3: Cross multiply
   1,408.72x = 2,113.84 × 668.16
4. Step 4: Simplify right side
   1,408.72x = 1,412,383.33
5. Step 5: Solve for x
   x = 1,412,383.33/1,408.72
6. Step 6: Final answer
   x = 1,002.60