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Finding the Fourth Proportional to 615.20, 849.86 and 490.69

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Solution

The fourth proportional to 615.20, 849.86 and 490.69 is: 677.86

Step by Step Solution

  1. Step 1: Write the proportion equation
    615.20 : 849.86 = 490.69 : x
  2. Step 2: Convert to fraction form
    615.20/849.86 = 490.69/x
  3. Step 3: Cross multiply
    615.20x = 849.86 × 490.69
  4. Step 4: Simplify right side
    615.20x = 417,018.25
  5. Step 5: Solve for x
    x = 417,018.25/615.20
  6. Step 6: Final answer
    x = 677.86

Related Problems

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Double scale
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1.5x scale

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.