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Finding the Fourth Proportional to 813.50, 1,219.49 and 265.40

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Solution

The fourth proportional to 813.50, 1,219.49 and 265.40 is: 397.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    813.50 : 1,219.49 = 265.40 : x
  2. Step 2: Convert to fraction form
    813.50/1,219.49 = 265.40/x
  3. Step 3: Cross multiply
    813.50x = 1,219.49 × 265.40
  4. Step 4: Simplify right side
    813.50x = 323,646.55
  5. Step 5: Solve for x
    x = 323,646.55/813.50
  6. Step 6: Final answer
    x = 397.85

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Double scale
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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.