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Finding the Fourth Proportional to 289.79, 401.95 and 279.42

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Solution

The fourth proportional to 289.79, 401.95 and 279.42 is: 387.57

Step by Step Solution

  1. Step 1: Write the proportion equation
    289.79 : 401.95 = 279.42 : x
  2. Step 2: Convert to fraction form
    289.79/401.95 = 279.42/x
  3. Step 3: Cross multiply
    289.79x = 401.95 × 279.42
  4. Step 4: Simplify right side
    289.79x = 112,312.87
  5. Step 5: Solve for x
    x = 112,312.87/289.79
  6. Step 6: Final answer
    x = 387.57

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Why These Related Problems?

These problems maintain the same ratio (1.39) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.