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Finding the Fourth Proportional to 813.35, 1,220.21 and 286.29

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Solution

The fourth proportional to 813.35, 1,220.21 and 286.29 is: 429.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    813.35 : 1,220.21 = 286.29 : x
  2. Step 2: Convert to fraction form
    813.35/1,220.21 = 286.29/x
  3. Step 3: Cross multiply
    813.35x = 1,220.21 × 286.29
  4. Step 4: Simplify right side
    813.35x = 349,332.49
  5. Step 5: Solve for x
    x = 349,332.49/813.35
  6. Step 6: Final answer
    x = 429.50

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