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Finding the Fourth Proportional to 65.10, 90.26 and 57.90

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Solution

The fourth proportional to 65.10, 90.26 and 57.90 is: 80.27

Step by Step Solution

  1. Step 1: Write the proportion equation
    65.10 : 90.26 = 57.90 : x
  2. Step 2: Convert to fraction form
    65.10/90.26 = 57.90/x
  3. Step 3: Cross multiply
    65.10x = 90.26 × 57.90
  4. Step 4: Simplify right side
    65.10x = 5,225.76
  5. Step 5: Solve for x
    x = 5,225.76/65.10
  6. Step 6: Final answer
    x = 80.27

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Why These Related Problems?

These problems maintain the same ratio (1.39) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.