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Finding the Fourth Proportional to 639.03, 957.99 and 330.72

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Solution

The fourth proportional to 639.03, 957.99 and 330.72 is: 495.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.03 : 957.99 = 330.72 : x
  2. Step 2: Convert to fraction form
    639.03/957.99 = 330.72/x
  3. Step 3: Cross multiply
    639.03x = 957.99 × 330.72
  4. Step 4: Simplify right side
    639.03x = 316,826.45
  5. Step 5: Solve for x
    x = 316,826.45/639.03
  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.