Finding the Fourth Proportional to 1,216.72, 1,678.91 and 692.76

Step by Step Solution

1. Step 1: Write the proportion equation
   1,216.72 : 1,678.91 = 692.76 : x
2. Step 2: Convert to fraction form
   1,216.72/1,678.91 = 692.76/x
3. Step 3: Cross multiply
   1,216.72x = 1,678.91 × 692.76
4. Step 4: Simplify right side
   1,216.72x = 1,163,081.69
5. Step 5: Solve for x
   x = 1,163,081.69/1,216.72
6. Step 6: Final answer
   x = 955.92