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Finding the Fourth Proportional to 285.21, 393.32 and 186.80

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Solution

The fourth proportional to 285.21, 393.32 and 186.80 is: 257.60

Step by Step Solution

  1. Step 1: Write the proportion equation
    285.21 : 393.32 = 186.80 : x
  2. Step 2: Convert to fraction form
    285.21/393.32 = 186.80/x
  3. Step 3: Cross multiply
    285.21x = 393.32 × 186.80
  4. Step 4: Simplify right side
    285.21x = 73,470.68
  5. Step 5: Solve for x
    x = 73,470.68/285.21
  6. Step 6: Final answer
    x = 257.60

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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.