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Finding the Fourth Proportional to 103.02, 142.08 and 71.88

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Solution

The fourth proportional to 103.02, 142.08 and 71.88 is: 99.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    103.02 : 142.08 = 71.88 : x
  2. Step 2: Convert to fraction form
    103.02/142.08 = 71.88/x
  3. Step 3: Cross multiply
    103.02x = 142.08 × 71.88
  4. Step 4: Simplify right side
    103.02x = 10,212.71
  5. Step 5: Solve for x
    x = 10,212.71/103.02
  6. Step 6: Final answer
    x = 99.13

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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.