Finding the Fourth Proportional to 1,019.16, 1,406.70 and 665.52

Step by Step Solution

1. Step 1: Write the proportion equation
   1,019.16 : 1,406.70 = 665.52 : x
2. Step 2: Convert to fraction form
   1,019.16/1,406.70 = 665.52/x
3. Step 3: Cross multiply
   1,019.16x = 1,406.70 × 665.52
4. Step 4: Simplify right side
   1,019.16x = 936,186.98
5. Step 5: Solve for x
   x = 936,186.98/1,019.16
6. Step 6: Final answer
   x = 918.59