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Finding the Fourth Proportional to 615.70, 850.69 and 485.70

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Solution

The fourth proportional to 615.70, 850.69 and 485.70 is: 671.07

Step by Step Solution

  1. Step 1: Write the proportion equation
    615.70 : 850.69 = 485.70 : x
  2. Step 2: Convert to fraction form
    615.70/850.69 = 485.70/x
  3. Step 3: Cross multiply
    615.70x = 850.69 × 485.70
  4. Step 4: Simplify right side
    615.70x = 413,180.13
  5. Step 5: Solve for x
    x = 413,180.13/615.70
  6. Step 6: Final answer
    x = 671.07

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.