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Finding the Fourth Proportional to 285.90, 394.29 and 186.21

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Solution

The fourth proportional to 285.90, 394.29 and 186.21 is: 256.81

Step by Step Solution

  1. Step 1: Write the proportion equation
    285.90 : 394.29 = 186.21 : x
  2. Step 2: Convert to fraction form
    285.90/394.29 = 186.21/x
  3. Step 3: Cross multiply
    285.90x = 394.29 × 186.21
  4. Step 4: Simplify right side
    285.90x = 73,420.74
  5. Step 5: Solve for x
    x = 73,420.74/285.90
  6. Step 6: Final answer
    x = 256.81

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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.