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Finding the Fourth Proportional to 285.64, 394.32 and 215.74

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Solution

The fourth proportional to 285.64, 394.32 and 215.74 is: 297.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    285.64 : 394.32 = 215.74 : x
  2. Step 2: Convert to fraction form
    285.64/394.32 = 215.74/x
  3. Step 3: Cross multiply
    285.64x = 394.32 × 215.74
  4. Step 4: Simplify right side
    285.64x = 85,068.63
  5. Step 5: Solve for x
    x = 85,068.63/285.64
  6. Step 6: Final answer
    x = 297.82

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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.