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Finding the Fourth Proportional to 420.98, 630.48 and 406.38

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Solution

The fourth proportional to 420.98, 630.48 and 406.38 is: 608.62

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.98 : 630.48 = 406.38 : x
  2. Step 2: Convert to fraction form
    420.98/630.48 = 406.38/x
  3. Step 3: Cross multiply
    420.98x = 630.48 × 406.38
  4. Step 4: Simplify right side
    420.98x = 256,214.46
  5. Step 5: Solve for x
    x = 256,214.46/420.98
  6. Step 6: Final answer
    x = 608.62

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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.