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Finding the Fourth Proportional to 89.09, 123.05 and 70.64

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Solution

The fourth proportional to 89.09, 123.05 and 70.64 is: 97.57

Step by Step Solution

  1. Step 1: Write the proportion equation
    89.09 : 123.05 = 70.64 : x
  2. Step 2: Convert to fraction form
    89.09/123.05 = 70.64/x
  3. Step 3: Cross multiply
    89.09x = 123.05 × 70.64
  4. Step 4: Simplify right side
    89.09x = 8,692.14
  5. Step 5: Solve for x
    x = 8,692.14/89.09
  6. Step 6: Final answer
    x = 97.57

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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.