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Finding the Fourth Proportional to 421.42, 581.82 and 310.70

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Solution

The fourth proportional to 421.42, 581.82 and 310.70 is: 428.96

Step by Step Solution

  1. Step 1: Write the proportion equation
    421.42 : 581.82 = 310.70 : x
  2. Step 2: Convert to fraction form
    421.42/581.82 = 310.70/x
  3. Step 3: Cross multiply
    421.42x = 581.82 × 310.70
  4. Step 4: Simplify right side
    421.42x = 180,771.47
  5. Step 5: Solve for x
    x = 180,771.47/421.42
  6. Step 6: Final answer
    x = 428.96

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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.