Finding the Fourth Proportional to 1,538.38, 2,121.15 and 1,242.73

Step by Step Solution

1. Step 1: Write the proportion equation
   1,538.38 : 2,121.15 = 1,242.73 : x
2. Step 2: Convert to fraction form
   1,538.38/2,121.15 = 1,242.73/x
3. Step 3: Cross multiply
   1,538.38x = 2,121.15 × 1,242.73
4. Step 4: Simplify right side
   1,538.38x = 2,636,016.74
5. Step 5: Solve for x
   x = 2,636,016.74/1,538.38
6. Step 6: Final answer
   x = 1,713.50