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Finding the Fourth Proportional to 80.42, 120.49 and 56.25

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Solution

The fourth proportional to 80.42, 120.49 and 56.25 is: 84.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    80.42 : 120.49 = 56.25 : x
  2. Step 2: Convert to fraction form
    80.42/120.49 = 56.25/x
  3. Step 3: Cross multiply
    80.42x = 120.49 × 56.25
  4. Step 4: Simplify right side
    80.42x = 6,777.42
  5. Step 5: Solve for x
    x = 6,777.42/80.42
  6. Step 6: Final answer
    x = 84.28

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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.