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Finding the Fourth Proportional to 285.77, 428.72 and 103.20

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Solution

The fourth proportional to 285.77, 428.72 and 103.20 is: 154.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    285.77 : 428.72 = 103.20 : x
  2. Step 2: Convert to fraction form
    285.77/428.72 = 103.20/x
  3. Step 3: Cross multiply
    285.77x = 428.72 × 103.20
  4. Step 4: Simplify right side
    285.77x = 44,243.39
  5. Step 5: Solve for x
    x = 44,243.39/285.77
  6. Step 6: Final answer
    x = 154.82

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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.