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Finding the Fourth Proportional to 228.29, 315.02 and 128.68

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Solution

The fourth proportional to 228.29, 315.02 and 128.68 is: 177.57

Step by Step Solution

  1. Step 1: Write the proportion equation
    228.29 : 315.02 = 128.68 : x
  2. Step 2: Convert to fraction form
    228.29/315.02 = 128.68/x
  3. Step 3: Cross multiply
    228.29x = 315.02 × 128.68
  4. Step 4: Simplify right side
    228.29x = 40,536.13
  5. Step 5: Solve for x
    x = 40,536.13/228.29
  6. Step 6: Final answer
    x = 177.57

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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.