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Finding the Fourth Proportional to 712.89, 983.81 and 398.19

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Solution

The fourth proportional to 712.89, 983.81 and 398.19 is: 549.51

Step by Step Solution

  1. Step 1: Write the proportion equation
    712.89 : 983.81 = 398.19 : x
  2. Step 2: Convert to fraction form
    712.89/983.81 = 398.19/x
  3. Step 3: Cross multiply
    712.89x = 983.81 × 398.19
  4. Step 4: Simplify right side
    712.89x = 391,743.30
  5. Step 5: Solve for x
    x = 391,743.30/712.89
  6. Step 6: Final answer
    x = 549.51

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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.