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Finding the Fourth Proportional to 872.42, 1,308.30 and 439.28

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Solution

The fourth proportional to 872.42, 1,308.30 and 439.28 is: 658.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    872.42 : 1,308.30 = 439.28 : x
  2. Step 2: Convert to fraction form
    872.42/1,308.30 = 439.28/x
  3. Step 3: Cross multiply
    872.42x = 1,308.30 × 439.28
  4. Step 4: Simplify right side
    872.42x = 574,710.02
  5. Step 5: Solve for x
    x = 574,710.02/872.42
  6. Step 6: Final answer
    x = 658.75

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.