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Finding the Fourth Proportional to 90.39, 135.09 and 59.70

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Solution

The fourth proportional to 90.39, 135.09 and 59.70 is: 89.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    90.39 : 135.09 = 59.70 : x
  2. Step 2: Convert to fraction form
    90.39/135.09 = 59.70/x
  3. Step 3: Cross multiply
    90.39x = 135.09 × 59.70
  4. Step 4: Simplify right side
    90.39x = 8,064.87
  5. Step 5: Solve for x
    x = 8,064.87/90.39
  6. Step 6: Final answer
    x = 89.22

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.