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Finding the Fourth Proportional to 639.02, 957.71 and 330.81

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Solution

The fourth proportional to 639.02, 957.71 and 330.81 is: 495.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.02 : 957.71 = 330.81 : x
  2. Step 2: Convert to fraction form
    639.02/957.71 = 330.81/x
  3. Step 3: Cross multiply
    639.02x = 957.71 × 330.81
  4. Step 4: Simplify right side
    639.02x = 316,818.39
  5. Step 5: Solve for x
    x = 316,818.39/639.02
  6. Step 6: Final answer
    x = 495.79

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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.