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Finding the Fourth Proportional to 388.99, 583.80 and 280.81

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Solution

The fourth proportional to 388.99, 583.80 and 280.81 is: 421.44

Step by Step Solution

  1. Step 1: Write the proportion equation
    388.99 : 583.80 = 280.81 : x
  2. Step 2: Convert to fraction form
    388.99/583.80 = 280.81/x
  3. Step 3: Cross multiply
    388.99x = 583.80 × 280.81
  4. Step 4: Simplify right side
    388.99x = 163,936.88
  5. Step 5: Solve for x
    x = 163,936.88/388.99
  6. Step 6: Final answer
    x = 421.44

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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.