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Finding the Fourth Proportional to 388.30, 535.86 and 220.28

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Solution

The fourth proportional to 388.30, 535.86 and 220.28 is: 303.99

Step by Step Solution

  1. Step 1: Write the proportion equation
    388.30 : 535.86 = 220.28 : x
  2. Step 2: Convert to fraction form
    388.30/535.86 = 220.28/x
  3. Step 3: Cross multiply
    388.30x = 535.86 × 220.28
  4. Step 4: Simplify right side
    388.30x = 118,039.24
  5. Step 5: Solve for x
    x = 118,039.24/388.30
  6. Step 6: Final answer
    x = 303.99

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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.