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Finding the Fourth Proportional to 421.21, 579.87 and 365.72

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Solution

The fourth proportional to 421.21, 579.87 and 365.72 is: 503.48

Step by Step Solution

  1. Step 1: Write the proportion equation
    421.21 : 579.87 = 365.72 : x
  2. Step 2: Convert to fraction form
    421.21/579.87 = 365.72/x
  3. Step 3: Cross multiply
    421.21x = 579.87 × 365.72
  4. Step 4: Simplify right side
    421.21x = 212,070.06
  5. Step 5: Solve for x
    x = 212,070.06/421.21
  6. Step 6: Final answer
    x = 503.48

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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.