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Finding the Fourth Proportional to 520.38, 718.13 and 287.51

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Solution

The fourth proportional to 520.38, 718.13 and 287.51 is: 396.76

Step by Step Solution

  1. Step 1: Write the proportion equation
    520.38 : 718.13 = 287.51 : x
  2. Step 2: Convert to fraction form
    520.38/718.13 = 287.51/x
  3. Step 3: Cross multiply
    520.38x = 718.13 × 287.51
  4. Step 4: Simplify right side
    520.38x = 206,466.68
  5. Step 5: Solve for x
    x = 206,466.68/520.38
  6. Step 6: Final answer
    x = 396.76

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Double scale
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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.