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Finding the Fourth Proportional to 420.37, 579.95 and 310.11

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Solution

The fourth proportional to 420.37, 579.95 and 310.11 is: 427.83

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.37 : 579.95 = 310.11 : x
  2. Step 2: Convert to fraction form
    420.37/579.95 = 310.11/x
  3. Step 3: Cross multiply
    420.37x = 579.95 × 310.11
  4. Step 4: Simplify right side
    420.37x = 179,849.07
  5. Step 5: Solve for x
    x = 179,849.07/420.37
  6. Step 6: Final answer
    x = 427.83

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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.