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Finding the Fourth Proportional to 65.21, 90.02 and 43.40

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Solution

The fourth proportional to 65.21, 90.02 and 43.40 is: 59.91

Step by Step Solution

  1. Step 1: Write the proportion equation
    65.21 : 90.02 = 43.40 : x
  2. Step 2: Convert to fraction form
    65.21/90.02 = 43.40/x
  3. Step 3: Cross multiply
    65.21x = 90.02 × 43.40
  4. Step 4: Simplify right side
    65.21x = 3,906.20
  5. Step 5: Solve for x
    x = 3,906.20/65.21
  6. Step 6: Final answer
    x = 59.91

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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.