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Finding the Fourth Proportional to 521.09, 781.65 and 131.09

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Solution

The fourth proportional to 521.09, 781.65 and 131.09 is: 196.64

Step by Step Solution

  1. Step 1: Write the proportion equation
    521.09 : 781.65 = 131.09 : x
  2. Step 2: Convert to fraction form
    521.09/781.65 = 131.09/x
  3. Step 3: Cross multiply
    521.09x = 781.65 × 131.09
  4. Step 4: Simplify right side
    521.09x = 102,466.50
  5. Step 5: Solve for x
    x = 102,466.50/521.09
  6. Step 6: Final answer
    x = 196.64

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Double scale
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Similar ratio
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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.