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Finding the Fourth Proportional to 65.40, 98.01 and 28.80

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Solution

The fourth proportional to 65.40, 98.01 and 28.80 is: 43.16

Step by Step Solution

  1. Step 1: Write the proportion equation
    65.40 : 98.01 = 28.80 : x
  2. Step 2: Convert to fraction form
    65.40/98.01 = 28.80/x
  3. Step 3: Cross multiply
    65.40x = 98.01 × 28.80
  4. Step 4: Simplify right side
    65.40x = 2,822.69
  5. Step 5: Solve for x
    x = 2,822.69/65.40
  6. Step 6: Final answer
    x = 43.16

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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.