Finding the Fourth Proportional to 1,009.86, 1,514.59 and 279.42

Step by Step Solution

1. Step 1: Write the proportion equation
   1,009.86 : 1,514.59 = 279.42 : x
2. Step 2: Convert to fraction form
   1,009.86/1,514.59 = 279.42/x
3. Step 3: Cross multiply
   1,009.86x = 1,514.59 × 279.42
4. Step 4: Simplify right side
   1,009.86x = 423,206.04
5. Step 5: Solve for x
   x = 423,206.04/1,009.86
6. Step 6: Final answer
   x = 419.07