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Finding the Fourth Proportional to 619.25, 854.42 and 420.10

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Solution

The fourth proportional to 619.25, 854.42 and 420.10 is: 579.65

Step by Step Solution

  1. Step 1: Write the proportion equation
    619.25 : 854.42 = 420.10 : x
  2. Step 2: Convert to fraction form
    619.25/854.42 = 420.10/x
  3. Step 3: Cross multiply
    619.25x = 854.42 × 420.10
  4. Step 4: Simplify right side
    619.25x = 358,942.41
  5. Step 5: Solve for x
    x = 358,942.41/619.25
  6. Step 6: Final answer
    x = 579.65

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.