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Finding the Fourth Proportional to 639, 957.60 and 330.12

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Solution

The fourth proportional to 639, 957.60 and 330.12 is: 494.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    639 : 957.60 = 330.12 : x
  2. Step 2: Convert to fraction form
    639/957.60 = 330.12/x
  3. Step 3: Cross multiply
    639x = 957.60 × 330.12
  4. Step 4: Simplify right side
    639x = 316,122.91
  5. Step 5: Solve for x
    x = 316,122.91/639
  6. Step 6: Final answer
    x = 494.72

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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.