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Finding the Fourth Proportional to 68.40, 102.07 and 61.10

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Solution

The fourth proportional to 68.40, 102.07 and 61.10 is: 91.17

Step by Step Solution

  1. Step 1: Write the proportion equation
    68.40 : 102.07 = 61.10 : x
  2. Step 2: Convert to fraction form
    68.40/102.07 = 61.10/x
  3. Step 3: Cross multiply
    68.40x = 102.07 × 61.10
  4. Step 4: Simplify right side
    68.40x = 6,235.81
  5. Step 5: Solve for x
    x = 6,235.81/68.40
  6. Step 6: Final answer
    x = 91.17

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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.