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Finding the Fourth Proportional to 282.40, 420.68 and 257.44

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Solution

The fourth proportional to 282.40, 420.68 and 257.44 is: 383.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    282.40 : 420.68 = 257.44 : x
  2. Step 2: Convert to fraction form
    282.40/420.68 = 257.44/x
  3. Step 3: Cross multiply
    282.40x = 420.68 × 257.44
  4. Step 4: Simplify right side
    282.40x = 108,299.86
  5. Step 5: Solve for x
    x = 108,299.86/282.40
  6. Step 6: Final answer
    x = 383.50

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.