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Finding the Fourth Proportional to 75.07, 103.36 and 65.21

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Solution

The fourth proportional to 75.07, 103.36 and 65.21 is: 89.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    75.07 : 103.36 = 65.21 : x
  2. Step 2: Convert to fraction form
    75.07/103.36 = 65.21/x
  3. Step 3: Cross multiply
    75.07x = 103.36 × 65.21
  4. Step 4: Simplify right side
    75.07x = 6,740.11
  5. Step 5: Solve for x
    x = 6,740.11/75.07
  6. Step 6: Final answer
    x = 89.78

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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.