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Finding the Fourth Proportional to 388.79, 536.97 and 257.57

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Solution

The fourth proportional to 388.79, 536.97 and 257.57 is: 355.74

Step by Step Solution

  1. Step 1: Write the proportion equation
    388.79 : 536.97 = 257.57 : x
  2. Step 2: Convert to fraction form
    388.79/536.97 = 257.57/x
  3. Step 3: Cross multiply
    388.79x = 536.97 × 257.57
  4. Step 4: Simplify right side
    388.79x = 138,304.68
  5. Step 5: Solve for x
    x = 138,304.68/388.79
  6. Step 6: Final answer
    x = 355.74

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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.