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Finding the Fourth Proportional to 618.27, 853.53 and 420.15

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Solution

The fourth proportional to 618.27, 853.53 and 420.15 is: 580.02

Step by Step Solution

  1. Step 1: Write the proportion equation
    618.27 : 853.53 = 420.15 : x
  2. Step 2: Convert to fraction form
    618.27/853.53 = 420.15/x
  3. Step 3: Cross multiply
    618.27x = 853.53 × 420.15
  4. Step 4: Simplify right side
    618.27x = 358,610.63
  5. Step 5: Solve for x
    x = 358,610.63/618.27
  6. Step 6: Final answer
    x = 580.02

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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.