Finding the Fourth Proportional to 1,219.50, 1,682.91 and 667.50

Step by Step Solution

1. Step 1: Write the proportion equation
   1,219.50 : 1,682.91 = 667.50 : x
2. Step 2: Convert to fraction form
   1,219.50/1,682.91 = 667.50/x
3. Step 3: Cross multiply
   1,219.50x = 1,682.91 × 667.50
4. Step 4: Simplify right side
   1,219.50x = 1,123,342.43
5. Step 5: Solve for x
   x = 1,123,342.43/1,219.50
6. Step 6: Final answer
   x = 921.15