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Finding the Fourth Proportional to 687.10, 947.96 and 477.20

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Solution

The fourth proportional to 687.10, 947.96 and 477.20 is: 658.37

Step by Step Solution

  1. Step 1: Write the proportion equation
    687.10 : 947.96 = 477.20 : x
  2. Step 2: Convert to fraction form
    687.10/947.96 = 477.20/x
  3. Step 3: Cross multiply
    687.10x = 947.96 × 477.20
  4. Step 4: Simplify right side
    687.10x = 452,366.51
  5. Step 5: Solve for x
    x = 452,366.51/687.10
  6. Step 6: Final answer
    x = 658.37

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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.