Finding the Fourth Proportional to 1,572.42, 2,169.98 and 909.50

Step by Step Solution

1. Step 1: Write the proportion equation
   1,572.42 : 2,169.98 = 909.50 : x
2. Step 2: Convert to fraction form
   1,572.42/2,169.98 = 909.50/x
3. Step 3: Cross multiply
   1,572.42x = 2,169.98 × 909.50
4. Step 4: Simplify right side
   1,572.42x = 1,973,604.51
5. Step 5: Solve for x
   x = 1,973,604.51/1,572.42
6. Step 6: Final answer
   x = 1,255.14