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Finding the Fourth Proportional to 388.47, 583.05 and 280.34

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Solution

The fourth proportional to 388.47, 583.05 and 280.34 is: 420.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    388.47 : 583.05 = 280.34 : x
  2. Step 2: Convert to fraction form
    388.47/583.05 = 280.34/x
  3. Step 3: Cross multiply
    388.47x = 583.05 × 280.34
  4. Step 4: Simplify right side
    388.47x = 163,449.32
  5. Step 5: Solve for x
    x = 163,449.32/388.47
  6. Step 6: Final answer
    x = 420.75

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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.