Finding the Fourth Proportional to 1,315.68, 1,974.72 and 585.12

Step by Step Solution

1. Step 1: Write the proportion equation
   1,315.68 : 1,974.72 = 585.12 : x
2. Step 2: Convert to fraction form
   1,315.68/1,974.72 = 585.12/x
3. Step 3: Cross multiply
   1,315.68x = 1,974.72 × 585.12
4. Step 4: Simplify right side
   1,315.68x = 1,155,448.17
5. Step 5: Solve for x
   x = 1,155,448.17/1,315.68
6. Step 6: Final answer
   x = 878.21