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Finding the Fourth Proportional to 665.88, 999.06 and 638.28

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Solution

The fourth proportional to 665.88, 999.06 and 638.28 is: 957.65

Step by Step Solution

  1. Step 1: Write the proportion equation
    665.88 : 999.06 = 638.28 : x
  2. Step 2: Convert to fraction form
    665.88/999.06 = 638.28/x
  3. Step 3: Cross multiply
    665.88x = 999.06 × 638.28
  4. Step 4: Simplify right side
    665.88x = 637,680.02
  5. Step 5: Solve for x
    x = 637,680.02/665.88
  6. Step 6: Final answer
    x = 957.65

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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.