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Finding the Fourth Proportional to 70.47, 106.31 and 65.61

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Solution

The fourth proportional to 70.47, 106.31 and 65.61 is: 98.98

Step by Step Solution

  1. Step 1: Write the proportion equation
    70.47 : 106.31 = 65.61 : x
  2. Step 2: Convert to fraction form
    70.47/106.31 = 65.61/x
  3. Step 3: Cross multiply
    70.47x = 106.31 × 65.61
  4. Step 4: Simplify right side
    70.47x = 6,975.16
  5. Step 5: Solve for x
    x = 6,975.16/70.47
  6. Step 6: Final answer
    x = 98.98

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.