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Finding the Fourth Proportional to 813.50, 1,220.10 and 380.56

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Solution

The fourth proportional to 813.50, 1,220.10 and 380.56 is: 570.77

Step by Step Solution

  1. Step 1: Write the proportion equation
    813.50 : 1,220.10 = 380.56 : x
  2. Step 2: Convert to fraction form
    813.50/1,220.10 = 380.56/x
  3. Step 3: Cross multiply
    813.50x = 1,220.10 × 380.56
  4. Step 4: Simplify right side
    813.50x = 464,321.26
  5. Step 5: Solve for x
    x = 464,321.26/813.50
  6. Step 6: Final answer
    x = 570.77

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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.