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Finding the Fourth Proportional to 220.50, 304.29 and 128.50

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Solution

The fourth proportional to 220.50, 304.29 and 128.50 is: 177.33

Step by Step Solution

  1. Step 1: Write the proportion equation
    220.50 : 304.29 = 128.50 : x
  2. Step 2: Convert to fraction form
    220.50/304.29 = 128.50/x
  3. Step 3: Cross multiply
    220.50x = 304.29 × 128.50
  4. Step 4: Simplify right side
    220.50x = 39,101.27
  5. Step 5: Solve for x
    x = 39,101.27/220.50
  6. Step 6: Final answer
    x = 177.33

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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.