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Finding the Fourth Proportional to 420.70, 580.82 and 281.02

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Solution

The fourth proportional to 420.70, 580.82 and 281.02 is: 387.98

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.70 : 580.82 = 281.02 : x
  2. Step 2: Convert to fraction form
    420.70/580.82 = 281.02/x
  3. Step 3: Cross multiply
    420.70x = 580.82 × 281.02
  4. Step 4: Simplify right side
    420.70x = 163,222.04
  5. Step 5: Solve for x
    x = 163,222.04/420.70
  6. Step 6: Final answer
    x = 387.98

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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.