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Finding the Fourth Proportional to 805.10, 1,207.55 and 220.15

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Solution

The fourth proportional to 805.10, 1,207.55 and 220.15 is: 330.19

Step by Step Solution

  1. Step 1: Write the proportion equation
    805.10 : 1,207.55 = 220.15 : x
  2. Step 2: Convert to fraction form
    805.10/1,207.55 = 220.15/x
  3. Step 3: Cross multiply
    805.10x = 1,207.55 × 220.15
  4. Step 4: Simplify right side
    805.10x = 265,839.66
  5. Step 5: Solve for x
    x = 265,839.66/805.10
  6. Step 6: Final answer
    x = 330.19

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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.