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Finding the Fourth Proportional to 645.30, 967.58 and 279.89

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Solution

The fourth proportional to 645.30, 967.58 and 279.89 is: 419.67

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.30 : 967.58 = 279.89 : x
  2. Step 2: Convert to fraction form
    645.30/967.58 = 279.89/x
  3. Step 3: Cross multiply
    645.30x = 967.58 × 279.89
  4. Step 4: Simplify right side
    645.30x = 270,815.97
  5. Step 5: Solve for x
    x = 270,815.97/645.30
  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.