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Finding the Fourth Proportional to 70.09, 105 and 53.86

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Solution

The fourth proportional to 70.09, 105 and 53.86 is: 80.69

Step by Step Solution

  1. Step 1: Write the proportion equation
    70.09 : 105 = 53.86 : x
  2. Step 2: Convert to fraction form
    70.09/105 = 53.86/x
  3. Step 3: Cross multiply
    70.09x = 105 × 53.86
  4. Step 4: Simplify right side
    70.09x = 5,655.30
  5. Step 5: Solve for x
    x = 5,655.30/70.09
  6. Step 6: Final answer
    x = 80.69

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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.