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Finding the Fourth Proportional to 640.45, 883.60 and 407.71

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Solution

The fourth proportional to 640.45, 883.60 and 407.71 is: 562.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.45 : 883.60 = 407.71 : x
  2. Step 2: Convert to fraction form
    640.45/883.60 = 407.71/x
  3. Step 3: Cross multiply
    640.45x = 883.60 × 407.71
  4. Step 4: Simplify right side
    640.45x = 360,252.56
  5. Step 5: Solve for x
    x = 360,252.56/640.45
  6. Step 6: Final answer
    x = 562.50

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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.