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Finding the Fourth Proportional to 419.47, 628.84 and 211.09

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Solution

The fourth proportional to 419.47, 628.84 and 211.09 is: 316.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    419.47 : 628.84 = 211.09 : x
  2. Step 2: Convert to fraction form
    419.47/628.84 = 211.09/x
  3. Step 3: Cross multiply
    419.47x = 628.84 × 211.09
  4. Step 4: Simplify right side
    419.47x = 132,741.84
  5. Step 5: Solve for x
    x = 132,741.84/419.47
  6. Step 6: Final answer
    x = 316.45

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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.