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Finding the Fourth Proportional to 279.47, 419.21 and 142.35

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Solution

The fourth proportional to 279.47, 419.21 and 142.35 is: 213.53

Step by Step Solution

  1. Step 1: Write the proportion equation
    279.47 : 419.21 = 142.35 : x
  2. Step 2: Convert to fraction form
    279.47/419.21 = 142.35/x
  3. Step 3: Cross multiply
    279.47x = 419.21 × 142.35
  4. Step 4: Simplify right side
    279.47x = 59,674.54
  5. Step 5: Solve for x
    x = 59,674.54/279.47
  6. Step 6: Final answer
    x = 213.53

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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.