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Finding the Fourth Proportional to 664.50, 996.75 and 279.78

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Solution

The fourth proportional to 664.50, 996.75 and 279.78 is: 419.67

Step by Step Solution

  1. Step 1: Write the proportion equation
    664.50 : 996.75 = 279.78 : x
  2. Step 2: Convert to fraction form
    664.50/996.75 = 279.78/x
  3. Step 3: Cross multiply
    664.50x = 996.75 × 279.78
  4. Step 4: Simplify right side
    664.50x = 278,870.72
  5. Step 5: Solve for x
    x = 278,870.72/664.50
  6. Step 6: Final answer
    x = 419.67

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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.