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Finding the Fourth Proportional to 698.38, 963.78 and 387.88

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Solution

The fourth proportional to 698.38, 963.78 and 387.88 is: 535.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    698.38 : 963.78 = 387.88 : x
  2. Step 2: Convert to fraction form
    698.38/963.78 = 387.88/x
  3. Step 3: Cross multiply
    698.38x = 963.78 × 387.88
  4. Step 4: Simplify right side
    698.38x = 373,830.99
  5. Step 5: Solve for x
    x = 373,830.99/698.38
  6. Step 6: Final answer
    x = 535.28

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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.