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Finding the Fourth Proportional to 419.39, 628.88 and 145.38

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Solution

The fourth proportional to 419.39, 628.88 and 145.38 is: 218.00

Step by Step Solution

  1. Step 1: Write the proportion equation
    419.39 : 628.88 = 145.38 : x
  2. Step 2: Convert to fraction form
    419.39/628.88 = 145.38/x
  3. Step 3: Cross multiply
    419.39x = 628.88 × 145.38
  4. Step 4: Simplify right side
    419.39x = 91,425.85
  5. Step 5: Solve for x
    x = 91,425.85/419.39
  6. Step 6: Final answer
    x = 218.00

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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.