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Finding the Fourth Proportional to 618.69, 854.45 and 420.41

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Solution

The fourth proportional to 618.69, 854.45 and 420.41 is: 580.61

Step by Step Solution

  1. Step 1: Write the proportion equation
    618.69 : 854.45 = 420.41 : x
  2. Step 2: Convert to fraction form
    618.69/854.45 = 420.41/x
  3. Step 3: Cross multiply
    618.69x = 854.45 × 420.41
  4. Step 4: Simplify right side
    618.69x = 359,214.53
  5. Step 5: Solve for x
    x = 359,214.53/618.69
  6. Step 6: Final answer
    x = 580.61

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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.