Finding the Fourth Proportional to 1,178.74, 1,626.72 and 667.76

Step by Step Solution

1. Step 1: Write the proportion equation
   1,178.74 : 1,626.72 = 667.76 : x
2. Step 2: Convert to fraction form
   1,178.74/1,626.72 = 667.76/x
3. Step 3: Cross multiply
   1,178.74x = 1,626.72 × 667.76
4. Step 4: Simplify right side
   1,178.74x = 1,086,258.55
5. Step 5: Solve for x
   x = 1,086,258.55/1,178.74
6. Step 6: Final answer
   x = 921.55