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Finding the Fourth Proportional to 521.79, 720.06 and 285.77

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Solution

The fourth proportional to 521.79, 720.06 and 285.77 is: 394.35

Step by Step Solution

  1. Step 1: Write the proportion equation
    521.79 : 720.06 = 285.77 : x
  2. Step 2: Convert to fraction form
    521.79/720.06 = 285.77/x
  3. Step 3: Cross multiply
    521.79x = 720.06 × 285.77
  4. Step 4: Simplify right side
    521.79x = 205,767.95
  5. Step 5: Solve for x
    x = 205,767.95/521.79
  6. Step 6: Final answer
    x = 394.35

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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.