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Finding the Fourth Proportional to 289.28, 430.85 and 287.88

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Solution

The fourth proportional to 289.28, 430.85 and 287.88 is: 428.77

Step by Step Solution

  1. Step 1: Write the proportion equation
    289.28 : 430.85 = 287.88 : x
  2. Step 2: Convert to fraction form
    289.28/430.85 = 287.88/x
  3. Step 3: Cross multiply
    289.28x = 430.85 × 287.88
  4. Step 4: Simplify right side
    289.28x = 124,033.82
  5. Step 5: Solve for x
    x = 124,033.82/289.28
  6. Step 6: Final answer
    x = 428.77

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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.