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Finding the Fourth Proportional to 420.88, 580.64 and 265.60

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Solution

The fourth proportional to 420.88, 580.64 and 265.60 is: 366.42

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.88 : 580.64 = 265.60 : x
  2. Step 2: Convert to fraction form
    420.88/580.64 = 265.60/x
  3. Step 3: Cross multiply
    420.88x = 580.64 × 265.60
  4. Step 4: Simplify right side
    420.88x = 154,217.98
  5. Step 5: Solve for x
    x = 154,217.98/420.88
  6. Step 6: Final answer
    x = 366.42

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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.