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Finding the Fourth Proportional to 419.78, 630.89 and 203.51

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Solution

The fourth proportional to 419.78, 630.89 and 203.51 is: 305.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    419.78 : 630.89 = 203.51 : x
  2. Step 2: Convert to fraction form
    419.78/630.89 = 203.51/x
  3. Step 3: Cross multiply
    419.78x = 630.89 × 203.51
  4. Step 4: Simplify right side
    419.78x = 128,388.25
  5. Step 5: Solve for x
    x = 128,388.25/419.78
  6. Step 6: Final answer
    x = 305.85

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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.