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Finding the Fourth Proportional to 290.64, 435.40 and 218.80

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Solution

The fourth proportional to 290.64, 435.40 and 218.80 is: 327.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    290.64 : 435.40 = 218.80 : x
  2. Step 2: Convert to fraction form
    290.64/435.40 = 218.80/x
  3. Step 3: Cross multiply
    290.64x = 435.40 × 218.80
  4. Step 4: Simplify right side
    290.64x = 95,265.52
  5. Step 5: Solve for x
    x = 95,265.52/290.64
  6. Step 6: Final answer
    x = 327.78

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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.