Finding the Fourth Proportional to 1,315.50, 1,974.32 and 666.42

Step by Step Solution

1. Step 1: Write the proportion equation
   1,315.50 : 1,974.32 = 666.42 : x
2. Step 2: Convert to fraction form
   1,315.50/1,974.32 = 666.42/x
3. Step 3: Cross multiply
   1,315.50x = 1,974.32 × 666.42
4. Step 4: Simplify right side
   1,315.50x = 1,315,726.33
5. Step 5: Solve for x
   x = 1,315,726.33/1,315.50
6. Step 6: Final answer
   x = 1,000.17