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Finding the Fourth Proportional to 120.09, 165.87 and 89.13

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Solution

The fourth proportional to 120.09, 165.87 and 89.13 is: 123.11

Step by Step Solution

  1. Step 1: Write the proportion equation
    120.09 : 165.87 = 89.13 : x
  2. Step 2: Convert to fraction form
    120.09/165.87 = 89.13/x
  3. Step 3: Cross multiply
    120.09x = 165.87 × 89.13
  4. Step 4: Simplify right side
    120.09x = 14,783.99
  5. Step 5: Solve for x
    x = 14,783.99/120.09
  6. Step 6: Final answer
    x = 123.11

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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.