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Finding the Fourth Proportional to 70.61, 105.30 and 65.75

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Solution

The fourth proportional to 70.61, 105.30 and 65.75 is: 98.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    70.61 : 105.30 = 65.75 : x
  2. Step 2: Convert to fraction form
    70.61/105.30 = 65.75/x
  3. Step 3: Cross multiply
    70.61x = 105.30 × 65.75
  4. Step 4: Simplify right side
    70.61x = 6,922.95
  5. Step 5: Solve for x
    x = 6,922.95/70.61
  6. Step 6: Final answer
    x = 98.05

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.