Finding the Fourth Proportional to 1,810.72, 2,715.60 and 511.88

Step by Step Solution

1. Step 1: Write the proportion equation
   1,810.72 : 2,715.60 = 511.88 : x
2. Step 2: Convert to fraction form
   1,810.72/2,715.60 = 511.88/x
3. Step 3: Cross multiply
   1,810.72x = 2,715.60 × 511.88
4. Step 4: Simplify right side
   1,810.72x = 1,390,061.33
5. Step 5: Solve for x
   x = 1,390,061.33/1,810.72
6. Step 6: Final answer
   x = 767.68