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Finding the Fourth Proportional to 421.91, 581.82 and 380.89

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Solution

The fourth proportional to 421.91, 581.82 and 380.89 is: 525.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    421.91 : 581.82 = 380.89 : x
  2. Step 2: Convert to fraction form
    421.91/581.82 = 380.89/x
  3. Step 3: Cross multiply
    421.91x = 581.82 × 380.89
  4. Step 4: Simplify right side
    421.91x = 221,609.42
  5. Step 5: Solve for x
    x = 221,609.42/421.91
  6. Step 6: Final answer
    x = 525.25

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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.