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Finding the Fourth Proportional to 287.20, 430.80 and 200.80

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Solution

The fourth proportional to 287.20, 430.80 and 200.80 is: 301.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    287.20 : 430.80 = 200.80 : x
  2. Step 2: Convert to fraction form
    287.20/430.80 = 200.80/x
  3. Step 3: Cross multiply
    287.20x = 430.80 × 200.80
  4. Step 4: Simplify right side
    287.20x = 86,504.64
  5. Step 5: Solve for x
    x = 86,504.64/287.20
  6. Step 6: Final answer
    x = 301.20

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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.