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Finding the Fourth Proportional to 103.07, 141.90 and 78.35

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Solution

The fourth proportional to 103.07, 141.90 and 78.35 is: 107.87

Step by Step Solution

  1. Step 1: Write the proportion equation
    103.07 : 141.90 = 78.35 : x
  2. Step 2: Convert to fraction form
    103.07/141.90 = 78.35/x
  3. Step 3: Cross multiply
    103.07x = 141.90 × 78.35
  4. Step 4: Simplify right side
    103.07x = 11,117.87
  5. Step 5: Solve for x
    x = 11,117.87/103.07
  6. Step 6: Final answer
    x = 107.87

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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.