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Finding the Fourth Proportional to 103.17, 142.58 and 84.72

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Solution

The fourth proportional to 103.17, 142.58 and 84.72 is: 117.08

Step by Step Solution

  1. Step 1: Write the proportion equation
    103.17 : 142.58 = 84.72 : x
  2. Step 2: Convert to fraction form
    103.17/142.58 = 84.72/x
  3. Step 3: Cross multiply
    103.17x = 142.58 × 84.72
  4. Step 4: Simplify right side
    103.17x = 12,079.38
  5. Step 5: Solve for x
    x = 12,079.38/103.17
  6. Step 6: Final answer
    x = 117.08

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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.