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Finding the Fourth Proportional to 640.54, 885.57 and 445.51

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Solution

The fourth proportional to 640.54, 885.57 and 445.51 is: 615.93

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.54 : 885.57 = 445.51 : x
  2. Step 2: Convert to fraction form
    640.54/885.57 = 445.51/x
  3. Step 3: Cross multiply
    640.54x = 885.57 × 445.51
  4. Step 4: Simplify right side
    640.54x = 394,530.29
  5. Step 5: Solve for x
    x = 394,530.29/640.54
  6. Step 6: Final answer
    x = 615.93

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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.