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Finding the Fourth Proportional to 388.64, 582.86 and 215.12

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Solution

The fourth proportional to 388.64, 582.86 and 215.12 is: 322.62

Step by Step Solution

  1. Step 1: Write the proportion equation
    388.64 : 582.86 = 215.12 : x
  2. Step 2: Convert to fraction form
    388.64/582.86 = 215.12/x
  3. Step 3: Cross multiply
    388.64x = 582.86 × 215.12
  4. Step 4: Simplify right side
    388.64x = 125,384.84
  5. Step 5: Solve for x
    x = 125,384.84/388.64
  6. Step 6: Final answer
    x = 322.62

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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.