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Finding the Fourth Proportional to 807.70, 1,211.21 and 307.05

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Solution

The fourth proportional to 807.70, 1,211.21 and 307.05 is: 460.44

Step by Step Solution

  1. Step 1: Write the proportion equation
    807.70 : 1,211.21 = 307.05 : x
  2. Step 2: Convert to fraction form
    807.70/1,211.21 = 307.05/x
  3. Step 3: Cross multiply
    807.70x = 1,211.21 × 307.05
  4. Step 4: Simplify right side
    807.70x = 371,894.44
  5. Step 5: Solve for x
    x = 371,894.44/807.70
  6. Step 6: Final answer
    x = 460.44

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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.