Finding the Fourth Proportional to 1,238.82, 1,858.55 and 913.62

Step by Step Solution

1. Step 1: Write the proportion equation
   1,238.82 : 1,858.55 = 913.62 : x
2. Step 2: Convert to fraction form
   1,238.82/1,858.55 = 913.62/x
3. Step 3: Cross multiply
   1,238.82x = 1,858.55 × 913.62
4. Step 4: Simplify right side
   1,238.82x = 1,698,010.85
5. Step 5: Solve for x
   x = 1,698,010.85/1,238.82
6. Step 6: Final answer
   x = 1,370.67