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Finding the Fourth Proportional to 419.12, 628.20 and 256.88

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Solution

The fourth proportional to 419.12, 628.20 and 256.88 is: 385.03

Step by Step Solution

  1. Step 1: Write the proportion equation
    419.12 : 628.20 = 256.88 : x
  2. Step 2: Convert to fraction form
    419.12/628.20 = 256.88/x
  3. Step 3: Cross multiply
    419.12x = 628.20 × 256.88
  4. Step 4: Simplify right side
    419.12x = 161,372.02
  5. Step 5: Solve for x
    x = 161,372.02/419.12
  6. Step 6: Final answer
    x = 385.03

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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.