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Finding the Fourth Proportional to 521.86, 720.16 and 285.81

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Solution

The fourth proportional to 521.86, 720.16 and 285.81 is: 394.41

Step by Step Solution

  1. Step 1: Write the proportion equation
    521.86 : 720.16 = 285.81 : x
  2. Step 2: Convert to fraction form
    521.86/720.16 = 285.81/x
  3. Step 3: Cross multiply
    521.86x = 720.16 × 285.81
  4. Step 4: Simplify right side
    521.86x = 205,828.93
  5. Step 5: Solve for x
    x = 205,828.93/521.86
  6. Step 6: Final answer
    x = 394.41

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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.