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Finding the Fourth Proportional to 65.33, 90.20 and 40.79

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Solution

The fourth proportional to 65.33, 90.20 and 40.79 is: 56.31

Step by Step Solution

  1. Step 1: Write the proportion equation
    65.33 : 90.20 = 40.79 : x
  2. Step 2: Convert to fraction form
    65.33/90.20 = 40.79/x
  3. Step 3: Cross multiply
    65.33x = 90.20 × 40.79
  4. Step 4: Simplify right side
    65.33x = 3,679.05
  5. Step 5: Solve for x
    x = 3,679.05/65.33
  6. Step 6: Final answer
    x = 56.31

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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.