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Finding the Fourth Proportional to 279.70, 385.67 and 253.78

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Solution

The fourth proportional to 279.70, 385.67 and 253.78 is: 349.92

Step by Step Solution

  1. Step 1: Write the proportion equation
    279.70 : 385.67 = 253.78 : x
  2. Step 2: Convert to fraction form
    279.70/385.67 = 253.78/x
  3. Step 3: Cross multiply
    279.70x = 385.67 × 253.78
  4. Step 4: Simplify right side
    279.70x = 97,872.14
  5. Step 5: Solve for x
    x = 97,872.14/279.70
  6. Step 6: Final answer
    x = 349.92

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.