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Finding the Fourth Proportional to 287.13, 430.09 and 280.25

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Solution

The fourth proportional to 287.13, 430.09 and 280.25 is: 419.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    287.13 : 430.09 = 280.25 : x
  2. Step 2: Convert to fraction form
    287.13/430.09 = 280.25/x
  3. Step 3: Cross multiply
    287.13x = 430.09 × 280.25
  4. Step 4: Simplify right side
    287.13x = 120,532.72
  5. Step 5: Solve for x
    x = 120,532.72/287.13
  6. Step 6: Final answer
    x = 419.78

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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.