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Finding the Fourth Proportional to 279.70, 419.58 and 218.72

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Solution

The fourth proportional to 279.70, 419.58 and 218.72 is: 328.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    279.70 : 419.58 = 218.72 : x
  2. Step 2: Convert to fraction form
    279.70/419.58 = 218.72/x
  3. Step 3: Cross multiply
    279.70x = 419.58 × 218.72
  4. Step 4: Simplify right side
    279.70x = 91,770.54
  5. Step 5: Solve for x
    x = 91,770.54/279.70
  6. Step 6: Final answer
    x = 328.10

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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.