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Finding the Fourth Proportional to 660.39, 990.38 and 617.25

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Solution

The fourth proportional to 660.39, 990.38 and 617.25 is: 925.68

Step by Step Solution

  1. Step 1: Write the proportion equation
    660.39 : 990.38 = 617.25 : x
  2. Step 2: Convert to fraction form
    660.39/990.38 = 617.25/x
  3. Step 3: Cross multiply
    660.39x = 990.38 × 617.25
  4. Step 4: Simplify right side
    660.39x = 611,308.97
  5. Step 5: Solve for x
    x = 611,308.97/660.39
  6. Step 6: Final answer
    x = 925.68

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.