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Finding the Fourth Proportional to 689.45, 951.42 and 378.95

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Solution

The fourth proportional to 689.45, 951.42 and 378.95 is: 522.94

Step by Step Solution

  1. Step 1: Write the proportion equation
    689.45 : 951.42 = 378.95 : x
  2. Step 2: Convert to fraction form
    689.45/951.42 = 378.95/x
  3. Step 3: Cross multiply
    689.45x = 951.42 × 378.95
  4. Step 4: Simplify right side
    689.45x = 360,535.85
  5. Step 5: Solve for x
    x = 360,535.85/689.45
  6. Step 6: Final answer
    x = 522.94

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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.