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Finding the Fourth Proportional to 685.60, 946.38 and 612.70

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Solution

The fourth proportional to 685.60, 946.38 and 612.70 is: 845.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    685.60 : 946.38 = 612.70 : x
  2. Step 2: Convert to fraction form
    685.60/946.38 = 612.70/x
  3. Step 3: Cross multiply
    685.60x = 946.38 × 612.70
  4. Step 4: Simplify right side
    685.60x = 579,846.96
  5. Step 5: Solve for x
    x = 579,846.96/685.60
  6. Step 6: Final answer
    x = 845.75

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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.