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Finding the Fourth Proportional to 664.78, 921.58 and 629.65

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Solution

The fourth proportional to 664.78, 921.58 and 629.65 is: 872.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    664.78 : 921.58 = 629.65 : x
  2. Step 2: Convert to fraction form
    664.78/921.58 = 629.65/x
  3. Step 3: Cross multiply
    664.78x = 921.58 × 629.65
  4. Step 4: Simplify right side
    664.78x = 580,272.85
  5. Step 5: Solve for x
    x = 580,272.85/664.78
  6. Step 6: Final answer
    x = 872.88

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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.39) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.