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Finding the Fourth Proportional to 78.52, 118.20 and 54.64

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Solution

The fourth proportional to 78.52, 118.20 and 54.64 is: 82.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    78.52 : 118.20 = 54.64 : x
  2. Step 2: Convert to fraction form
    78.52/118.20 = 54.64/x
  3. Step 3: Cross multiply
    78.52x = 118.20 × 54.64
  4. Step 4: Simplify right side
    78.52x = 6,458.45
  5. Step 5: Solve for x
    x = 6,458.45/78.52
  6. Step 6: Final answer
    x = 82.25

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.