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Finding the Fourth Proportional to 521.29, 719.40 and 285.25

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Solution

The fourth proportional to 521.29, 719.40 and 285.25 is: 393.66

Step by Step Solution

  1. Step 1: Write the proportion equation
    521.29 : 719.40 = 285.25 : x
  2. Step 2: Convert to fraction form
    521.29/719.40 = 285.25/x
  3. Step 3: Cross multiply
    521.29x = 719.40 × 285.25
  4. Step 4: Simplify right side
    521.29x = 205,208.85
  5. Step 5: Solve for x
    x = 205,208.85/521.29
  6. Step 6: Final answer
    x = 393.66

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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.