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Finding the Fourth Proportional to 419.72, 630.18 and 203.45

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Solution

The fourth proportional to 419.72, 630.18 and 203.45 is: 305.46

Step by Step Solution

  1. Step 1: Write the proportion equation
    419.72 : 630.18 = 203.45 : x
  2. Step 2: Convert to fraction form
    419.72/630.18 = 203.45/x
  3. Step 3: Cross multiply
    419.72x = 630.18 × 203.45
  4. Step 4: Simplify right side
    419.72x = 128,206.97
  5. Step 5: Solve for x
    x = 128,206.97/419.72
  6. Step 6: Final answer
    x = 305.46

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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.