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Finding the Fourth Proportional to 65.79, 90.65 and 60.39

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Solution

The fourth proportional to 65.79, 90.65 and 60.39 is: 83.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    65.79 : 90.65 = 60.39 : x
  2. Step 2: Convert to fraction form
    65.79/90.65 = 60.39/x
  3. Step 3: Cross multiply
    65.79x = 90.65 × 60.39
  4. Step 4: Simplify right side
    65.79x = 5,474.50
  5. Step 5: Solve for x
    x = 5,474.50/65.79
  6. Step 6: Final answer
    x = 83.21

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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.