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Finding the Fourth Proportional to 640.31, 884.06 and 490.67

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Solution

The fourth proportional to 640.31, 884.06 and 490.67 is: 677.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.31 : 884.06 = 490.67 : x
  2. Step 2: Convert to fraction form
    640.31/884.06 = 490.67/x
  3. Step 3: Cross multiply
    640.31x = 884.06 × 490.67
  4. Step 4: Simplify right side
    640.31x = 433,776.69
  5. Step 5: Solve for x
    x = 433,776.69/640.31
  6. Step 6: Final answer
    x = 677.45

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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.