Finding the Fourth Proportional to 1,005.22, 1,507.82 and 274.79

Step by Step Solution

1. Step 1: Write the proportion equation
   1,005.22 : 1,507.82 = 274.79 : x
2. Step 2: Convert to fraction form
   1,005.22/1,507.82 = 274.79/x
3. Step 3: Cross multiply
   1,005.22x = 1,507.82 × 274.79
4. Step 4: Simplify right side
   1,005.22x = 414,333.86
5. Step 5: Solve for x
   x = 414,333.86/1,005.22
6. Step 6: Final answer
   x = 412.18