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Finding the Fourth Proportional to 654.40, 897.21 and 642.71

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Solution

The fourth proportional to 654.40, 897.21 and 642.71 is: 881.18

Step by Step Solution

  1. Step 1: Write the proportion equation
    654.40 : 897.21 = 642.71 : x
  2. Step 2: Convert to fraction form
    654.40/897.21 = 642.71/x
  3. Step 3: Cross multiply
    654.40x = 897.21 × 642.71
  4. Step 4: Simplify right side
    654.40x = 576,641.35
  5. Step 5: Solve for x
    x = 576,641.35/654.40
  6. Step 6: Final answer
    x = 881.18

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.