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Finding the Fourth Proportional to 78.26, 108.14 and 53.78

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Solution

The fourth proportional to 78.26, 108.14 and 53.78 is: 74.31

Step by Step Solution

  1. Step 1: Write the proportion equation
    78.26 : 108.14 = 53.78 : x
  2. Step 2: Convert to fraction form
    78.26/108.14 = 53.78/x
  3. Step 3: Cross multiply
    78.26x = 108.14 × 53.78
  4. Step 4: Simplify right side
    78.26x = 5,814.96
  5. Step 5: Solve for x
    x = 5,814.96/78.26
  6. Step 6: Final answer
    x = 74.31

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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.