Finding the Fourth Proportional to 1,407.69, 2,111.53 and 381.69

Step by Step Solution

1. Step 1: Write the proportion equation
   1,407.69 : 2,111.53 = 381.69 : x
2. Step 2: Convert to fraction form
   1,407.69/2,111.53 = 381.69/x
3. Step 3: Cross multiply
   1,407.69x = 2,111.53 × 381.69
4. Step 4: Simplify right side
   1,407.69x = 805,949.89
5. Step 5: Solve for x
   x = 805,949.89/1,407.69
6. Step 6: Final answer
   x = 572.53