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Finding the Fourth Proportional to 285.71, 394.28 and 154.71

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Solution

The fourth proportional to 285.71, 394.28 and 154.71 is: 213.51

Step by Step Solution

  1. Step 1: Write the proportion equation
    285.71 : 394.28 = 154.71 : x
  2. Step 2: Convert to fraction form
    285.71/394.28 = 154.71/x
  3. Step 3: Cross multiply
    285.71x = 394.28 × 154.71
  4. Step 4: Simplify right side
    285.71x = 60,999.76
  5. Step 5: Solve for x
    x = 60,999.76/285.71
  6. Step 6: Final answer
    x = 213.51

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.