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Finding the Fourth Proportional to 687.97, 949.17 and 408.30

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Solution

The fourth proportional to 687.97, 949.17 and 408.30 is: 563.32

Step by Step Solution

  1. Step 1: Write the proportion equation
    687.97 : 949.17 = 408.30 : x
  2. Step 2: Convert to fraction form
    687.97/949.17 = 408.30/x
  3. Step 3: Cross multiply
    687.97x = 949.17 × 408.30
  4. Step 4: Simplify right side
    687.97x = 387,546.11
  5. Step 5: Solve for x
    x = 387,546.11/687.97
  6. Step 6: Final answer
    x = 563.32

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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.