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Finding the Fourth Proportional to 287.96, 428.56 and 278.24

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Solution

The fourth proportional to 287.96, 428.56 and 278.24 is: 414.09

Step by Step Solution

  1. Step 1: Write the proportion equation
    287.96 : 428.56 = 278.24 : x
  2. Step 2: Convert to fraction form
    287.96/428.56 = 278.24/x
  3. Step 3: Cross multiply
    287.96x = 428.56 × 278.24
  4. Step 4: Simplify right side
    287.96x = 119,239.70
  5. Step 5: Solve for x
    x = 119,239.70/287.96
  6. Step 6: Final answer
    x = 414.09

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.