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Finding the Fourth Proportional to 611.40, 917.39 and 286.72

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Solution

The fourth proportional to 611.40, 917.39 and 286.72 is: 430.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    611.40 : 917.39 = 286.72 : x
  2. Step 2: Convert to fraction form
    611.40/917.39 = 286.72/x
  3. Step 3: Cross multiply
    611.40x = 917.39 × 286.72
  4. Step 4: Simplify right side
    611.40x = 263,034.06
  5. Step 5: Solve for x
    x = 263,034.06/611.40
  6. Step 6: Final answer
    x = 430.22

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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 (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.