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Finding the Fourth Proportional to 520.47, 718.25 and 287.55

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Solution

The fourth proportional to 520.47, 718.25 and 287.55 is: 396.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    520.47 : 718.25 = 287.55 : x
  2. Step 2: Convert to fraction form
    520.47/718.25 = 287.55/x
  3. Step 3: Cross multiply
    520.47x = 718.25 × 287.55
  4. Step 4: Simplify right side
    520.47x = 206,531.35
  5. Step 5: Solve for x
    x = 206,531.35/520.47
  6. Step 6: Final answer
    x = 396.82

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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.