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Finding the Fourth Proportional to 285.72, 393.82 and 220.20

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Solution

The fourth proportional to 285.72, 393.82 and 220.20 is: 303.51

Step by Step Solution

  1. Step 1: Write the proportion equation
    285.72 : 393.82 = 220.20 : x
  2. Step 2: Convert to fraction form
    285.72/393.82 = 220.20/x
  3. Step 3: Cross multiply
    285.72x = 393.82 × 220.20
  4. Step 4: Simplify right side
    285.72x = 86,719.16
  5. Step 5: Solve for x
    x = 86,719.16/285.72
  6. Step 6: Final answer
    x = 303.51

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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.