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Finding the Fourth Proportional to 654.20, 903.22 and 405.78

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Solution

The fourth proportional to 654.20, 903.22 and 405.78 is: 560.24

Step by Step Solution

  1. Step 1: Write the proportion equation
    654.20 : 903.22 = 405.78 : x
  2. Step 2: Convert to fraction form
    654.20/903.22 = 405.78/x
  3. Step 3: Cross multiply
    654.20x = 903.22 × 405.78
  4. Step 4: Simplify right side
    654.20x = 366,506.58
  5. Step 5: Solve for x
    x = 366,506.58/654.20
  6. Step 6: Final answer
    x = 560.24

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.