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Finding the Fourth Proportional to 639.32, 957.92 and 330.72

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Solution

The fourth proportional to 639.32, 957.92 and 330.72 is: 495.53

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.32 : 957.92 = 330.72 : x
  2. Step 2: Convert to fraction form
    639.32/957.92 = 330.72/x
  3. Step 3: Cross multiply
    639.32x = 957.92 × 330.72
  4. Step 4: Simplify right side
    639.32x = 316,803.30
  5. Step 5: Solve for x
    x = 316,803.30/639.32
  6. Step 6: Final answer
    x = 495.53

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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.