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Finding the Fourth Proportional to 712.12, 982.80 and 397.42

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Solution

The fourth proportional to 712.12, 982.80 and 397.42 is: 548.48

Step by Step Solution

  1. Step 1: Write the proportion equation
    712.12 : 982.80 = 397.42 : x
  2. Step 2: Convert to fraction form
    712.12/982.80 = 397.42/x
  3. Step 3: Cross multiply
    712.12x = 982.80 × 397.42
  4. Step 4: Simplify right side
    712.12x = 390,584.38
  5. Step 5: Solve for x
    x = 390,584.38/712.12
  6. Step 6: Final answer
    x = 548.48

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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.