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Finding the Fourth Proportional to 159.81, 220.54 and 90.81

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Solution

The fourth proportional to 159.81, 220.54 and 90.81 is: 125.32

Step by Step Solution

  1. Step 1: Write the proportion equation
    159.81 : 220.54 = 90.81 : x
  2. Step 2: Convert to fraction form
    159.81/220.54 = 90.81/x
  3. Step 3: Cross multiply
    159.81x = 220.54 × 90.81
  4. Step 4: Simplify right side
    159.81x = 20,028.02
  5. Step 5: Solve for x
    x = 20,028.02/159.81
  6. Step 6: Final answer
    x = 125.32

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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.