Finding the Fourth Proportional to 1,145.72, 1,718.58 and 478.94

Step by Step Solution

1. Step 1: Write the proportion equation
   1,145.72 : 1,718.58 = 478.94 : x
2. Step 2: Convert to fraction form
   1,145.72/1,718.58 = 478.94/x
3. Step 3: Cross multiply
   1,145.72x = 1,718.58 × 478.94
4. Step 4: Simplify right side
   1,145.72x = 823,096.71
5. Step 5: Solve for x
   x = 823,096.71/1,145.72
6. Step 6: Final answer
   x = 718.41