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Finding the Fourth Proportional to 689.36, 951.36 and 378.86

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Solution

The fourth proportional to 689.36, 951.36 and 378.86 is: 522.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    689.36 : 951.36 = 378.86 : x
  2. Step 2: Convert to fraction form
    689.36/951.36 = 378.86/x
  3. Step 3: Cross multiply
    689.36x = 951.36 × 378.86
  4. Step 4: Simplify right side
    689.36x = 360,432.25
  5. Step 5: Solve for x
    x = 360,432.25/689.36
  6. Step 6: Final answer
    x = 522.85

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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.