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Finding the Fourth Proportional to 485.86, 670.66 and 320.15

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Solution

The fourth proportional to 485.86, 670.66 and 320.15 is: 441.91

Step by Step Solution

  1. Step 1: Write the proportion equation
    485.86 : 670.66 = 320.15 : x
  2. Step 2: Convert to fraction form
    485.86/670.66 = 320.15/x
  3. Step 3: Cross multiply
    485.86x = 670.66 × 320.15
  4. Step 4: Simplify right side
    485.86x = 214,708.45
  5. Step 5: Solve for x
    x = 214,708.45/485.86
  6. Step 6: Final answer
    x = 441.91

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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.