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Finding the Fourth Proportional to 419.88, 630.23 and 257.88

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Solution

The fourth proportional to 419.88, 630.23 and 257.88 is: 387.07

Step by Step Solution

  1. Step 1: Write the proportion equation
    419.88 : 630.23 = 257.88 : x
  2. Step 2: Convert to fraction form
    419.88/630.23 = 257.88/x
  3. Step 3: Cross multiply
    419.88x = 630.23 × 257.88
  4. Step 4: Simplify right side
    419.88x = 162,522.42
  5. Step 5: Solve for x
    x = 162,522.42/419.88
  6. Step 6: Final answer
    x = 387.07

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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.