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Finding the Fourth Proportional to 54.40, 82.08 and 51.20

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Solution

The fourth proportional to 54.40, 82.08 and 51.20 is: 77.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    54.40 : 82.08 = 51.20 : x
  2. Step 2: Convert to fraction form
    54.40/82.08 = 51.20/x
  3. Step 3: Cross multiply
    54.40x = 82.08 × 51.20
  4. Step 4: Simplify right side
    54.40x = 4,202.50
  5. Step 5: Solve for x
    x = 4,202.50/54.40
  6. Step 6: Final answer
    x = 77.25

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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.