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Finding the Fourth Proportional to 616.39, 851.70 and 505.78

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Solution

The fourth proportional to 616.39, 851.70 and 505.78 is: 698.86

Step by Step Solution

  1. Step 1: Write the proportion equation
    616.39 : 851.70 = 505.78 : x
  2. Step 2: Convert to fraction form
    616.39/851.70 = 505.78/x
  3. Step 3: Cross multiply
    616.39x = 851.70 × 505.78
  4. Step 4: Simplify right side
    616.39x = 430,772.83
  5. Step 5: Solve for x
    x = 430,772.83/616.39
  6. Step 6: Final answer
    x = 698.86

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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.