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Finding the Fourth Proportional to 711.84, 981.80 and 490.80

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Solution

The fourth proportional to 711.84, 981.80 and 490.80 is: 676.93

Step by Step Solution

  1. Step 1: Write the proportion equation
    711.84 : 981.80 = 490.80 : x
  2. Step 2: Convert to fraction form
    711.84/981.80 = 490.80/x
  3. Step 3: Cross multiply
    711.84x = 981.80 × 490.80
  4. Step 4: Simplify right side
    711.84x = 481,867.44
  5. Step 5: Solve for x
    x = 481,867.44/711.84
  6. Step 6: Final answer
    x = 676.93

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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.