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Finding the Fourth Proportional to 699.70, 981.20 and 699.70

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Solution

The fourth proportional to 699.70, 981.20 and 699.70 is: 981.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    699.70 : 981.20 = 699.70 : x
  2. Step 2: Convert to fraction form
    699.70/981.20 = 699.70/x
  3. Step 3: Cross multiply
    699.70x = 981.20 × 699.70
  4. Step 4: Simplify right side
    699.70x = 686,545.64
  5. Step 5: Solve for x
    x = 686,545.64/699.70
  6. Step 6: Final answer
    x = 981.20

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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.40) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.