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Finding the Fourth Proportional to 419.49, 628.80 and 199.71

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Solution

The fourth proportional to 419.49, 628.80 and 199.71 is: 299.36

Step by Step Solution

  1. Step 1: Write the proportion equation
    419.49 : 628.80 = 199.71 : x
  2. Step 2: Convert to fraction form
    419.49/628.80 = 199.71/x
  3. Step 3: Cross multiply
    419.49x = 628.80 × 199.71
  4. Step 4: Simplify right side
    419.49x = 125,577.65
  5. Step 5: Solve for x
    x = 125,577.65/419.49
  6. Step 6: Final answer
    x = 299.36

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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.