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Finding the Fourth Proportional to 52, 78 and 14

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Solution

The fourth proportional to 52, 78 and 14 is: 21

Step by Step Solution

  1. Step 1: Write the proportion equation
    52 : 78 = 14 : x
  2. Step 2: Convert to fraction form
    52/78 = 14/x
  3. Step 3: Cross multiply
    52x = 78 × 14
  4. Step 4: Simplify right side
    52x = 1,092
  5. Step 5: Solve for x
    x = 1,092/52
  6. Step 6: Final answer
    x = 21

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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.