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Finding the Fourth Proportional to 279.46, 419.19 and 87.09

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Solution

The fourth proportional to 279.46, 419.19 and 87.09 is: 130.64

Step by Step Solution

  1. Step 1: Write the proportion equation
    279.46 : 419.19 = 87.09 : x
  2. Step 2: Convert to fraction form
    279.46/419.19 = 87.09/x
  3. Step 3: Cross multiply
    279.46x = 419.19 × 87.09
  4. Step 4: Simplify right side
    279.46x = 36,507.26
  5. Step 5: Solve for x
    x = 36,507.26/279.46
  6. Step 6: Final answer
    x = 130.64

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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.