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Finding the Fourth Proportional to 687.97, 949.34 and 408.18

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Solution

The fourth proportional to 687.97, 949.34 and 408.18 is: 563.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    687.97 : 949.34 = 408.18 : x
  2. Step 2: Convert to fraction form
    687.97/949.34 = 408.18/x
  3. Step 3: Cross multiply
    687.97x = 949.34 × 408.18
  4. Step 4: Simplify right side
    687.97x = 387,501.60
  5. Step 5: Solve for x
    x = 387,501.60/687.97
  6. Step 6: Final answer
    x = 563.25

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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.