Finding the Fourth Proportional to 1,145.34, 1,718.72 and 451.89

Step by Step Solution

1. Step 1: Write the proportion equation
   1,145.34 : 1,718.72 = 451.89 : x
2. Step 2: Convert to fraction form
   1,145.34/1,718.72 = 451.89/x
3. Step 3: Cross multiply
   1,145.34x = 1,718.72 × 451.89
4. Step 4: Simplify right side
   1,145.34x = 776,670.12
5. Step 5: Solve for x
   x = 776,670.12/1,145.34
6. Step 6: Final answer
   x = 678.11