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Finding the Fourth Proportional to 687.25, 947.34 and 450.79

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Solution

The fourth proportional to 687.25, 947.34 and 450.79 is: 621.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    687.25 : 947.34 = 450.79 : x
  2. Step 2: Convert to fraction form
    687.25/947.34 = 450.79/x
  3. Step 3: Cross multiply
    687.25x = 947.34 × 450.79
  4. Step 4: Simplify right side
    687.25x = 427,051.40
  5. Step 5: Solve for x
    x = 427,051.40/687.25
  6. Step 6: Final answer
    x = 621.39

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Half scale
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Double scale
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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.