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Finding the Fourth Proportional to 401.80, 603.10 and 257.62

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Solution

The fourth proportional to 401.80, 603.10 and 257.62 is: 386.69

Step by Step Solution

  1. Step 1: Write the proportion equation
    401.80 : 603.10 = 257.62 : x
  2. Step 2: Convert to fraction form
    401.80/603.10 = 257.62/x
  3. Step 3: Cross multiply
    401.80x = 603.10 × 257.62
  4. Step 4: Simplify right side
    401.80x = 155,370.62
  5. Step 5: Solve for x
    x = 155,370.62/401.80
  6. Step 6: Final answer
    x = 386.69

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.