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Finding the Fourth Proportional to 665.89, 919.07 and 445.21

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Solution

The fourth proportional to 665.89, 919.07 and 445.21 is: 614.48

Step by Step Solution

  1. Step 1: Write the proportion equation
    665.89 : 919.07 = 445.21 : x
  2. Step 2: Convert to fraction form
    665.89/919.07 = 445.21/x
  3. Step 3: Cross multiply
    665.89x = 919.07 × 445.21
  4. Step 4: Simplify right side
    665.89x = 409,176.93
  5. Step 5: Solve for x
    x = 409,176.93/665.89
  6. Step 6: Final answer
    x = 614.48

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Double scale
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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.