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Finding the Fourth Proportional to 721.39, 995.11 and 488.11

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Solution

The fourth proportional to 721.39, 995.11 and 488.11 is: 673.32

Step by Step Solution

  1. Step 1: Write the proportion equation
    721.39 : 995.11 = 488.11 : x
  2. Step 2: Convert to fraction form
    721.39/995.11 = 488.11/x
  3. Step 3: Cross multiply
    721.39x = 995.11 × 488.11
  4. Step 4: Simplify right side
    721.39x = 485,723.14
  5. Step 5: Solve for x
    x = 485,723.14/721.39
  6. Step 6: Final answer
    x = 673.32

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1.5x scale

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.