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Finding the Fourth Proportional to 660.76, 991.98 and 418.30

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Solution

The fourth proportional to 660.76, 991.98 and 418.30 is: 627.98

Step by Step Solution

  1. Step 1: Write the proportion equation
    660.76 : 991.98 = 418.30 : x
  2. Step 2: Convert to fraction form
    660.76/991.98 = 418.30/x
  3. Step 3: Cross multiply
    660.76x = 991.98 × 418.30
  4. Step 4: Simplify right side
    660.76x = 414,945.23
  5. Step 5: Solve for x
    x = 414,945.23/660.76
  6. Step 6: Final answer
    x = 627.98

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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.