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Finding the Fourth Proportional to 70.63, 105.72 and 65.65

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Solution

The fourth proportional to 70.63, 105.72 and 65.65 is: 98.27

Step by Step Solution

  1. Step 1: Write the proportion equation
    70.63 : 105.72 = 65.65 : x
  2. Step 2: Convert to fraction form
    70.63/105.72 = 65.65/x
  3. Step 3: Cross multiply
    70.63x = 105.72 × 65.65
  4. Step 4: Simplify right side
    70.63x = 6,940.52
  5. Step 5: Solve for x
    x = 6,940.52/70.63
  6. Step 6: Final answer
    x = 98.27

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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.