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Finding the Fourth Proportional to 279.87, 419.64 and 142.81

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Solution

The fourth proportional to 279.87, 419.64 and 142.81 is: 214.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    279.87 : 419.64 = 142.81 : x
  2. Step 2: Convert to fraction form
    279.87/419.64 = 142.81/x
  3. Step 3: Cross multiply
    279.87x = 419.64 × 142.81
  4. Step 4: Simplify right side
    279.87x = 59,928.79
  5. Step 5: Solve for x
    x = 59,928.79/279.87
  6. Step 6: Final answer
    x = 214.13

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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.