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Finding the Fourth Proportional to 123.38, 170.21 and 70.91

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Solution

The fourth proportional to 123.38, 170.21 and 70.91 is: 97.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    123.38 : 170.21 = 70.91 : x
  2. Step 2: Convert to fraction form
    123.38/170.21 = 70.91/x
  3. Step 3: Cross multiply
    123.38x = 170.21 × 70.91
  4. Step 4: Simplify right side
    123.38x = 12,068.39
  5. Step 5: Solve for x
    x = 12,068.39/123.38
  6. Step 6: Final answer
    x = 97.82

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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.