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Finding the Fourth Proportional to 70.38, 105.18 and 64.91

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Solution

The fourth proportional to 70.38, 105.18 and 64.91 is: 97.00

Step by Step Solution

  1. Step 1: Write the proportion equation
    70.38 : 105.18 = 64.91 : x
  2. Step 2: Convert to fraction form
    70.38/105.18 = 64.91/x
  3. Step 3: Cross multiply
    70.38x = 105.18 × 64.91
  4. Step 4: Simplify right side
    70.38x = 6,827.03
  5. Step 5: Solve for x
    x = 6,827.03/70.38
  6. Step 6: Final answer
    x = 97.00

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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.