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Finding the Fourth Proportional to 813.49, 1,220.09 and 402.49

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Solution

The fourth proportional to 813.49, 1,220.09 and 402.49 is: 603.66

Step by Step Solution

  1. Step 1: Write the proportion equation
    813.49 : 1,220.09 = 402.49 : x
  2. Step 2: Convert to fraction form
    813.49/1,220.09 = 402.49/x
  3. Step 3: Cross multiply
    813.49x = 1,220.09 × 402.49
  4. Step 4: Simplify right side
    813.49x = 491,074.02
  5. Step 5: Solve for x
    x = 491,074.02/813.49
  6. Step 6: Final answer
    x = 603.66

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Double scale
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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.