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Finding the Fourth Proportional to 388.85, 583.35 and 145.45

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Solution

The fourth proportional to 388.85, 583.35 and 145.45 is: 218.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    388.85 : 583.35 = 145.45 : x
  2. Step 2: Convert to fraction form
    388.85/583.35 = 145.45/x
  3. Step 3: Cross multiply
    388.85x = 583.35 × 145.45
  4. Step 4: Simplify right side
    388.85x = 84,845.98
  5. Step 5: Solve for x
    x = 84,845.98/388.85
  6. Step 6: Final answer
    x = 218.20

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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.