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Finding the Fourth Proportional to 711.20, 981.11 and 612.79

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Solution

The fourth proportional to 711.20, 981.11 and 612.79 is: 845.34

Step by Step Solution

  1. Step 1: Write the proportion equation
    711.20 : 981.11 = 612.79 : x
  2. Step 2: Convert to fraction form
    711.20/981.11 = 612.79/x
  3. Step 3: Cross multiply
    711.20x = 981.11 × 612.79
  4. Step 4: Simplify right side
    711.20x = 601,206.43
  5. Step 5: Solve for x
    x = 601,206.43/711.20
  6. Step 6: Final answer
    x = 845.34

Related Problems

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Half scale
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Double scale
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Similar ratio
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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.