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Finding the Fourth Proportional to 711.74, 981.90 and 449.70

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Solution

The fourth proportional to 711.74, 981.90 and 449.70 is: 620.40

Step by Step Solution

  1. Step 1: Write the proportion equation
    711.74 : 981.90 = 449.70 : x
  2. Step 2: Convert to fraction form
    711.74/981.90 = 449.70/x
  3. Step 3: Cross multiply
    711.74x = 981.90 × 449.70
  4. Step 4: Simplify right side
    711.74x = 441,560.43
  5. Step 5: Solve for x
    x = 441,560.43/711.74
  6. Step 6: Final answer
    x = 620.40

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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.