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Finding the Fourth Proportional to 287.49, 429.05 and 280.20

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Solution

The fourth proportional to 287.49, 429.05 and 280.20 is: 418.17

Step by Step Solution

  1. Step 1: Write the proportion equation
    287.49 : 429.05 = 280.20 : x
  2. Step 2: Convert to fraction form
    287.49/429.05 = 280.20/x
  3. Step 3: Cross multiply
    287.49x = 429.05 × 280.20
  4. Step 4: Simplify right side
    287.49x = 120,219.81
  5. Step 5: Solve for x
    x = 120,219.81/287.49
  6. Step 6: Final answer
    x = 418.17

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.