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Finding the Fourth Proportional to 103.08, 142.38 and 90.84

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Solution

The fourth proportional to 103.08, 142.38 and 90.84 is: 125.47

Step by Step Solution

  1. Step 1: Write the proportion equation
    103.08 : 142.38 = 90.84 : x
  2. Step 2: Convert to fraction form
    103.08/142.38 = 90.84/x
  3. Step 3: Cross multiply
    103.08x = 142.38 × 90.84
  4. Step 4: Simplify right side
    103.08x = 12,933.80
  5. Step 5: Solve for x
    x = 12,933.80/103.08
  6. Step 6: Final answer
    x = 125.47

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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.