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Finding the Fourth Proportional to 285.51, 394.11 and 187.20

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Solution

The fourth proportional to 285.51, 394.11 and 187.20 is: 258.41

Step by Step Solution

  1. Step 1: Write the proportion equation
    285.51 : 394.11 = 187.20 : x
  2. Step 2: Convert to fraction form
    285.51/394.11 = 187.20/x
  3. Step 3: Cross multiply
    285.51x = 394.11 × 187.20
  4. Step 4: Simplify right side
    285.51x = 73,777.39
  5. Step 5: Solve for x
    x = 73,777.39/285.51
  6. Step 6: Final answer
    x = 258.41

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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.