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Finding the Fourth Proportional to 420.22, 579.42 and 313.91

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Solution

The fourth proportional to 420.22, 579.42 and 313.91 is: 432.83

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.22 : 579.42 = 313.91 : x
  2. Step 2: Convert to fraction form
    420.22/579.42 = 313.91/x
  3. Step 3: Cross multiply
    420.22x = 579.42 × 313.91
  4. Step 4: Simplify right side
    420.22x = 181,885.01
  5. Step 5: Solve for x
    x = 181,885.01/420.22
  6. Step 6: Final answer
    x = 432.83

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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.