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Finding the Fourth Proportional to 663.32, 995.81 and 420.86

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Solution

The fourth proportional to 663.32, 995.81 and 420.86 is: 631.81

Step by Step Solution

  1. Step 1: Write the proportion equation
    663.32 : 995.81 = 420.86 : x
  2. Step 2: Convert to fraction form
    663.32/995.81 = 420.86/x
  3. Step 3: Cross multiply
    663.32x = 995.81 × 420.86
  4. Step 4: Simplify right side
    663.32x = 419,096.98
  5. Step 5: Solve for x
    x = 419,096.98/663.32
  6. Step 6: Final answer
    x = 631.81

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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.