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Finding the Fourth Proportional to 388.28, 535.32 and 305.25

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Solution

The fourth proportional to 388.28, 535.32 and 305.25 is: 420.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    388.28 : 535.32 = 305.25 : x
  2. Step 2: Convert to fraction form
    388.28/535.32 = 305.25/x
  3. Step 3: Cross multiply
    388.28x = 535.32 × 305.25
  4. Step 4: Simplify right side
    388.28x = 163,406.43
  5. Step 5: Solve for x
    x = 163,406.43/388.28
  6. Step 6: Final answer
    x = 420.85

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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.