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Finding the Fourth Proportional to 102.09, 140.78 and 70.95

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Solution

The fourth proportional to 102.09, 140.78 and 70.95 is: 97.84

Step by Step Solution

  1. Step 1: Write the proportion equation
    102.09 : 140.78 = 70.95 : x
  2. Step 2: Convert to fraction form
    102.09/140.78 = 70.95/x
  3. Step 3: Cross multiply
    102.09x = 140.78 × 70.95
  4. Step 4: Simplify right side
    102.09x = 9,987.99
  5. Step 5: Solve for x
    x = 9,987.99/102.09
  6. Step 6: Final answer
    x = 97.84

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.