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Finding the Fourth Proportional to 698.70, 964.18 and 388.20

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Solution

The fourth proportional to 698.70, 964.18 and 388.20 is: 535.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    698.70 : 964.18 = 388.20 : x
  2. Step 2: Convert to fraction form
    698.70/964.18 = 388.20/x
  3. Step 3: Cross multiply
    698.70x = 964.18 × 388.20
  4. Step 4: Simplify right side
    698.70x = 374,294.68
  5. Step 5: Solve for x
    x = 374,294.68/698.70
  6. Step 6: Final answer
    x = 535.70

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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.