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Finding the Fourth Proportional to 388.86, 535.05 and 318.66

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Solution

The fourth proportional to 388.86, 535.05 and 318.66 is: 438.46

Step by Step Solution

  1. Step 1: Write the proportion equation
    388.86 : 535.05 = 318.66 : x
  2. Step 2: Convert to fraction form
    388.86/535.05 = 318.66/x
  3. Step 3: Cross multiply
    388.86x = 535.05 × 318.66
  4. Step 4: Simplify right side
    388.86x = 170,499.03
  5. Step 5: Solve for x
    x = 170,499.03/388.86
  6. Step 6: Final answer
    x = 438.46

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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.