Finding the Fourth Proportional to 1,215.50, 1,821.60 and 667.94

Step by Step Solution

1. Step 1: Write the proportion equation
   1,215.50 : 1,821.60 = 667.94 : x
2. Step 2: Convert to fraction form
   1,215.50/1,821.60 = 667.94/x
3. Step 3: Cross multiply
   1,215.50x = 1,821.60 × 667.94
4. Step 4: Simplify right side
   1,215.50x = 1,216,719.50
5. Step 5: Solve for x
   x = 1,216,719.50/1,215.50
6. Step 6: Final answer
   x = 1,001.00