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Finding the Fourth Proportional to 485.67, 670.32 and 289.25

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Solution

The fourth proportional to 485.67, 670.32 and 289.25 is: 399.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    485.67 : 670.32 = 289.25 : x
  2. Step 2: Convert to fraction form
    485.67/670.32 = 289.25/x
  3. Step 3: Cross multiply
    485.67x = 670.32 × 289.25
  4. Step 4: Simplify right side
    485.67x = 193,886.71
  5. Step 5: Solve for x
    x = 193,886.71/485.67
  6. Step 6: Final answer
    x = 399.21

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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.