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Finding the Fourth Proportional to 388.83, 583.26 and 128.71

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Solution

The fourth proportional to 388.83, 583.26 and 128.71 is: 193.07

Step by Step Solution

  1. Step 1: Write the proportion equation
    388.83 : 583.26 = 128.71 : x
  2. Step 2: Convert to fraction form
    388.83/583.26 = 128.71/x
  3. Step 3: Cross multiply
    388.83x = 583.26 × 128.71
  4. Step 4: Simplify right side
    388.83x = 75,071.39
  5. Step 5: Solve for x
    x = 75,071.39/388.83
  6. Step 6: Final answer
    x = 193.07

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.