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Finding the Fourth Proportional to 720.65, 994.79 and 487.91

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Solution

The fourth proportional to 720.65, 994.79 and 487.91 is: 673.51

Step by Step Solution

  1. Step 1: Write the proportion equation
    720.65 : 994.79 = 487.91 : x
  2. Step 2: Convert to fraction form
    720.65/994.79 = 487.91/x
  3. Step 3: Cross multiply
    720.65x = 994.79 × 487.91
  4. Step 4: Simplify right side
    720.65x = 485,367.99
  5. Step 5: Solve for x
    x = 485,367.99/720.65
  6. Step 6: Final answer
    x = 673.51

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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.