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Finding the Fourth Proportional to 388.70, 535.96 and 318.53

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Solution

The fourth proportional to 388.70, 535.96 and 318.53 is: 439.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    388.70 : 535.96 = 318.53 : x
  2. Step 2: Convert to fraction form
    388.70/535.96 = 318.53/x
  3. Step 3: Cross multiply
    388.70x = 535.96 × 318.53
  4. Step 4: Simplify right side
    388.70x = 170,719.88
  5. Step 5: Solve for x
    x = 170,719.88/388.70
  6. Step 6: Final answer
    x = 439.21

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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.