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Finding the Fourth Proportional to 717.60, 990.36 and 455.64

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Solution

The fourth proportional to 717.60, 990.36 and 455.64 is: 628.83

Step by Step Solution

  1. Step 1: Write the proportion equation
    717.60 : 990.36 = 455.64 : x
  2. Step 2: Convert to fraction form
    717.60/990.36 = 455.64/x
  3. Step 3: Cross multiply
    717.60x = 990.36 × 455.64
  4. Step 4: Simplify right side
    717.60x = 451,247.63
  5. Step 5: Solve for x
    x = 451,247.63/717.60
  6. Step 6: Final answer
    x = 628.83

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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.