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Finding the Fourth Proportional to 454.29, 678.14 and 420.45

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Solution

The fourth proportional to 454.29, 678.14 and 420.45 is: 627.62

Step by Step Solution

  1. Step 1: Write the proportion equation
    454.29 : 678.14 = 420.45 : x
  2. Step 2: Convert to fraction form
    454.29/678.14 = 420.45/x
  3. Step 3: Cross multiply
    454.29x = 678.14 × 420.45
  4. Step 4: Simplify right side
    454.29x = 285,118.47
  5. Step 5: Solve for x
    x = 285,118.47/454.29
  6. Step 6: Final answer
    x = 627.62

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.