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Finding the Fourth Proportional to 689.41, 951.38 and 378.91

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Solution

The fourth proportional to 689.41, 951.38 and 378.91 is: 522.89

Step by Step Solution

  1. Step 1: Write the proportion equation
    689.41 : 951.38 = 378.91 : x
  2. Step 2: Convert to fraction form
    689.41/951.38 = 378.91/x
  3. Step 3: Cross multiply
    689.41x = 951.38 × 378.91
  4. Step 4: Simplify right side
    689.41x = 360,487.40
  5. Step 5: Solve for x
    x = 360,487.40/689.41
  6. Step 6: Final answer
    x = 522.89

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1.5x scale

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.