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Finding the Fourth Proportional to 742.05, 1,112.81 and 279.74

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Solution

The fourth proportional to 742.05, 1,112.81 and 279.74 is: 419.51

Step by Step Solution

  1. Step 1: Write the proportion equation
    742.05 : 1,112.81 = 279.74 : x
  2. Step 2: Convert to fraction form
    742.05/1,112.81 = 279.74/x
  3. Step 3: Cross multiply
    742.05x = 1,112.81 × 279.74
  4. Step 4: Simplify right side
    742.05x = 311,298.85
  5. Step 5: Solve for x
    x = 311,298.85/742.05
  6. Step 6: Final answer
    x = 419.51

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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.