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Finding the Fourth Proportional to 720.80, 994.40 and 487.52

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Solution

The fourth proportional to 720.80, 994.40 and 487.52 is: 672.57

Step by Step Solution

  1. Step 1: Write the proportion equation
    720.80 : 994.40 = 487.52 : x
  2. Step 2: Convert to fraction form
    720.80/994.40 = 487.52/x
  3. Step 3: Cross multiply
    720.80x = 994.40 × 487.52
  4. Step 4: Simplify right side
    720.80x = 484,789.89
  5. Step 5: Solve for x
    x = 484,789.89/720.80
  6. Step 6: Final answer
    x = 672.57

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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.