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Finding the Fourth Proportional to 151.31, 208.80 and 89.13

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Solution

The fourth proportional to 151.31, 208.80 and 89.13 is: 122.99

Step by Step Solution

  1. Step 1: Write the proportion equation
    151.31 : 208.80 = 89.13 : x
  2. Step 2: Convert to fraction form
    151.31/208.80 = 89.13/x
  3. Step 3: Cross multiply
    151.31x = 208.80 × 89.13
  4. Step 4: Simplify right side
    151.31x = 18,610.34
  5. Step 5: Solve for x
    x = 18,610.34/151.31
  6. Step 6: Final answer
    x = 122.99

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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.