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Finding the Fourth Proportional to 70.40, 105.02 and 65.18

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Solution

The fourth proportional to 70.40, 105.02 and 65.18 is: 97.23

Step by Step Solution

  1. Step 1: Write the proportion equation
    70.40 : 105.02 = 65.18 : x
  2. Step 2: Convert to fraction form
    70.40/105.02 = 65.18/x
  3. Step 3: Cross multiply
    70.40x = 105.02 × 65.18
  4. Step 4: Simplify right side
    70.40x = 6,845.20
  5. Step 5: Solve for x
    x = 6,845.20/70.40
  6. Step 6: Final answer
    x = 97.23

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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.