Finding the Fourth Proportional to 1,379.52, 2,069.18 and 513.76

Step by Step Solution

1. Step 1: Write the proportion equation
   1,379.52 : 2,069.18 = 513.76 : x
2. Step 2: Convert to fraction form
   1,379.52/2,069.18 = 513.76/x
3. Step 3: Cross multiply
   1,379.52x = 2,069.18 × 513.76
4. Step 4: Simplify right side
   1,379.52x = 1,063,061.92
5. Step 5: Solve for x
   x = 1,063,061.92/1,379.52
6. Step 6: Final answer
   x = 770.60