Finding the Fourth Proportional to 1,370.67, 1,890.99 and 839.12

Step by Step Solution

1. Step 1: Write the proportion equation
   1,370.67 : 1,890.99 = 839.12 : x
2. Step 2: Convert to fraction form
   1,370.67/1,890.99 = 839.12/x
3. Step 3: Cross multiply
   1,370.67x = 1,890.99 × 839.12
4. Step 4: Simplify right side
   1,370.67x = 1,586,767.53
5. Step 5: Solve for x
   x = 1,586,767.53/1,370.67
6. Step 6: Final answer
   x = 1,157.66