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Finding the Fourth Proportional to 521.17, 719.20 and 285.12

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Solution

The fourth proportional to 521.17, 719.20 and 285.12 is: 393.46

Step by Step Solution

  1. Step 1: Write the proportion equation
    521.17 : 719.20 = 285.12 : x
  2. Step 2: Convert to fraction form
    521.17/719.20 = 285.12/x
  3. Step 3: Cross multiply
    521.17x = 719.20 × 285.12
  4. Step 4: Simplify right side
    521.17x = 205,058.30
  5. Step 5: Solve for x
    x = 205,058.30/521.17
  6. Step 6: Final answer
    x = 393.46

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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.