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Finding the Fourth Proportional to 639.65, 882.69 and 356.07

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Solution

The fourth proportional to 639.65, 882.69 and 356.07 is: 491.35

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.65 : 882.69 = 356.07 : x
  2. Step 2: Convert to fraction form
    639.65/882.69 = 356.07/x
  3. Step 3: Cross multiply
    639.65x = 882.69 × 356.07
  4. Step 4: Simplify right side
    639.65x = 314,295.01
  5. Step 5: Solve for x
    x = 314,295.01/639.65
  6. Step 6: Final answer
    x = 491.35

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.