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Finding the Fourth Proportional to 420.10, 579.89 and 310.46

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Solution

The fourth proportional to 420.10, 579.89 and 310.46 is: 428.54

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.10 : 579.89 = 310.46 : x
  2. Step 2: Convert to fraction form
    420.10/579.89 = 310.46/x
  3. Step 3: Cross multiply
    420.10x = 579.89 × 310.46
  4. Step 4: Simplify right side
    420.10x = 180,030.53
  5. Step 5: Solve for x
    x = 180,030.53/420.10
  6. Step 6: Final answer
    x = 428.54

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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.