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Finding the Fourth Proportional to 660.88, 989.40 and 402.64

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Solution

The fourth proportional to 660.88, 989.40 and 402.64 is: 602.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    660.88 : 989.40 = 402.64 : x
  2. Step 2: Convert to fraction form
    660.88/989.40 = 402.64/x
  3. Step 3: Cross multiply
    660.88x = 989.40 × 402.64
  4. Step 4: Simplify right side
    660.88x = 398,372.02
  5. Step 5: Solve for x
    x = 398,372.02/660.88
  6. Step 6: Final answer
    x = 602.79

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.