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Finding the Fourth Proportional to 290.64, 435.48 and 280.68

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Solution

The fourth proportional to 290.64, 435.48 and 280.68 is: 420.56

Step by Step Solution

  1. Step 1: Write the proportion equation
    290.64 : 435.48 = 280.68 : x
  2. Step 2: Convert to fraction form
    290.64/435.48 = 280.68/x
  3. Step 3: Cross multiply
    290.64x = 435.48 × 280.68
  4. Step 4: Simplify right side
    290.64x = 122,230.53
  5. Step 5: Solve for x
    x = 122,230.53/290.64
  6. Step 6: Final answer
    x = 420.56

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.