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Finding the Fourth Proportional to 521.29, 780.72 and 412.35

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Solution

The fourth proportional to 521.29, 780.72 and 412.35 is: 617.56

Step by Step Solution

  1. Step 1: Write the proportion equation
    521.29 : 780.72 = 412.35 : x
  2. Step 2: Convert to fraction form
    521.29/780.72 = 412.35/x
  3. Step 3: Cross multiply
    521.29x = 780.72 × 412.35
  4. Step 4: Simplify right side
    521.29x = 321,929.89
  5. Step 5: Solve for x
    x = 321,929.89/521.29
  6. Step 6: Final answer
    x = 617.56

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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.