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Finding the Fourth Proportional to 285.60, 394.07 and 215.64

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Solution

The fourth proportional to 285.60, 394.07 and 215.64 is: 297.53

Step by Step Solution

  1. Step 1: Write the proportion equation
    285.60 : 394.07 = 215.64 : x
  2. Step 2: Convert to fraction form
    285.60/394.07 = 215.64/x
  3. Step 3: Cross multiply
    285.60x = 394.07 × 215.64
  4. Step 4: Simplify right side
    285.60x = 84,975.07
  5. Step 5: Solve for x
    x = 84,975.07/285.60
  6. Step 6: Final answer
    x = 297.53

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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.