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Finding the Fourth Proportional to 72.45, 107.95 and 67.89

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Solution

The fourth proportional to 72.45, 107.95 and 67.89 is: 101.16

Step by Step Solution

  1. Step 1: Write the proportion equation
    72.45 : 107.95 = 67.89 : x
  2. Step 2: Convert to fraction form
    72.45/107.95 = 67.89/x
  3. Step 3: Cross multiply
    72.45x = 107.95 × 67.89
  4. Step 4: Simplify right side
    72.45x = 7,328.81
  5. Step 5: Solve for x
    x = 7,328.81/72.45
  6. Step 6: Final answer
    x = 101.16

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.