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Finding the Fourth Proportional to 70.40, 105.69 and 55.28

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Solution

The fourth proportional to 70.40, 105.69 and 55.28 is: 82.99

Step by Step Solution

  1. Step 1: Write the proportion equation
    70.40 : 105.69 = 55.28 : x
  2. Step 2: Convert to fraction form
    70.40/105.69 = 55.28/x
  3. Step 3: Cross multiply
    70.40x = 105.69 × 55.28
  4. Step 4: Simplify right side
    70.40x = 5,842.54
  5. Step 5: Solve for x
    x = 5,842.54/70.40
  6. Step 6: Final answer
    x = 82.99

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.