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Finding the Fourth Proportional to 478.98, 660.61 and 310.75

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Solution

The fourth proportional to 478.98, 660.61 and 310.75 is: 428.59

Step by Step Solution

  1. Step 1: Write the proportion equation
    478.98 : 660.61 = 310.75 : x
  2. Step 2: Convert to fraction form
    478.98/660.61 = 310.75/x
  3. Step 3: Cross multiply
    478.98x = 660.61 × 310.75
  4. Step 4: Simplify right side
    478.98x = 205,285.32
  5. Step 5: Solve for x
    x = 205,285.32/478.98
  6. Step 6: Final answer
    x = 428.59

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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.