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Finding the Fourth Proportional to 279.91, 419.79 and 84.91

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Solution

The fourth proportional to 279.91, 419.79 and 84.91 is: 127.34

Step by Step Solution

  1. Step 1: Write the proportion equation
    279.91 : 419.79 = 84.91 : x
  2. Step 2: Convert to fraction form
    279.91/419.79 = 84.91/x
  3. Step 3: Cross multiply
    279.91x = 419.79 × 84.91
  4. Step 4: Simplify right side
    279.91x = 35,644.37
  5. Step 5: Solve for x
    x = 35,644.37/279.91
  6. Step 6: Final answer
    x = 127.34

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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.