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Finding the Fourth Proportional to 128.98, 177.65 and 119.25

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Solution

The fourth proportional to 128.98, 177.65 and 119.25 is: 164.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    128.98 : 177.65 = 119.25 : x
  2. Step 2: Convert to fraction form
    128.98/177.65 = 119.25/x
  3. Step 3: Cross multiply
    128.98x = 177.65 × 119.25
  4. Step 4: Simplify right side
    128.98x = 21,184.17
  5. Step 5: Solve for x
    x = 21,184.17/128.98
  6. Step 6: Final answer
    x = 164.25

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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.