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Finding the Fourth Proportional to 638.84, 957.78 and 330.28

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Solution

The fourth proportional to 638.84, 957.78 and 330.28 is: 495.17

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.84 : 957.78 = 330.28 : x
  2. Step 2: Convert to fraction form
    638.84/957.78 = 330.28/x
  3. Step 3: Cross multiply
    638.84x = 957.78 × 330.28
  4. Step 4: Simplify right side
    638.84x = 316,335.58
  5. Step 5: Solve for x
    x = 316,335.58/638.84
  6. Step 6: Final answer
    x = 495.17

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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.