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Finding the Fourth Proportional to 388.28, 581.76 and 258.16

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Solution

The fourth proportional to 388.28, 581.76 and 258.16 is: 386.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    388.28 : 581.76 = 258.16 : x
  2. Step 2: Convert to fraction form
    388.28/581.76 = 258.16/x
  3. Step 3: Cross multiply
    388.28x = 581.76 × 258.16
  4. Step 4: Simplify right side
    388.28x = 150,187.16
  5. Step 5: Solve for x
    x = 150,187.16/388.28
  6. Step 6: Final answer
    x = 386.80

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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.