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Finding the Fourth Proportional to 420.56, 580.20 and 282.56

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Solution

The fourth proportional to 420.56, 580.20 and 282.56 is: 389.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.56 : 580.20 = 282.56 : x
  2. Step 2: Convert to fraction form
    420.56/580.20 = 282.56/x
  3. Step 3: Cross multiply
    420.56x = 580.20 × 282.56
  4. Step 4: Simplify right side
    420.56x = 163,941.31
  5. Step 5: Solve for x
    x = 163,941.31/420.56
  6. Step 6: Final answer
    x = 389.82

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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.