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Finding the Fourth Proportional to 420.35, 630.90 and 201.08

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Solution

The fourth proportional to 420.35, 630.90 and 201.08 is: 301.81

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.35 : 630.90 = 201.08 : x
  2. Step 2: Convert to fraction form
    420.35/630.90 = 201.08/x
  3. Step 3: Cross multiply
    420.35x = 630.90 × 201.08
  4. Step 4: Simplify right side
    420.35x = 126,862.95
  5. Step 5: Solve for x
    x = 126,862.95/420.35
  6. Step 6: Final answer
    x = 301.81

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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.