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Finding the Fourth Proportional to 687.48, 947.37 and 490.65

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Solution

The fourth proportional to 687.48, 947.37 and 490.65 is: 676.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    687.48 : 947.37 = 490.65 : x
  2. Step 2: Convert to fraction form
    687.48/947.37 = 490.65/x
  3. Step 3: Cross multiply
    687.48x = 947.37 × 490.65
  4. Step 4: Simplify right side
    687.48x = 464,827.09
  5. Step 5: Solve for x
    x = 464,827.09/687.48
  6. Step 6: Final answer
    x = 676.13

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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.