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Finding the Fourth Proportional to 485.82, 670.51 and 289.45

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Solution

The fourth proportional to 485.82, 670.51 and 289.45 is: 399.49

Step by Step Solution

  1. Step 1: Write the proportion equation
    485.82 : 670.51 = 289.45 : x
  2. Step 2: Convert to fraction form
    485.82/670.51 = 289.45/x
  3. Step 3: Cross multiply
    485.82x = 670.51 × 289.45
  4. Step 4: Simplify right side
    485.82x = 194,077.81
  5. Step 5: Solve for x
    x = 194,077.81/485.82
  6. Step 6: Final answer
    x = 399.49

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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.