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Finding the Fourth Proportional to 109.79, 151.31 and 89.02

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Solution

The fourth proportional to 109.79, 151.31 and 89.02 is: 122.68

Step by Step Solution

  1. Step 1: Write the proportion equation
    109.79 : 151.31 = 89.02 : x
  2. Step 2: Convert to fraction form
    109.79/151.31 = 89.02/x
  3. Step 3: Cross multiply
    109.79x = 151.31 × 89.02
  4. Step 4: Simplify right side
    109.79x = 13,468.41
  5. Step 5: Solve for x
    x = 13,468.41/109.79
  6. Step 6: Final answer
    x = 122.68

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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.