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Finding the Fourth Proportional to 485.29, 669.36 and 310.51

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Solution

The fourth proportional to 485.29, 669.36 and 310.51 is: 428.29

Step by Step Solution

  1. Step 1: Write the proportion equation
    485.29 : 669.36 = 310.51 : x
  2. Step 2: Convert to fraction form
    485.29/669.36 = 310.51/x
  3. Step 3: Cross multiply
    485.29x = 669.36 × 310.51
  4. Step 4: Simplify right side
    485.29x = 207,842.97
  5. Step 5: Solve for x
    x = 207,842.97/485.29
  6. Step 6: Final answer
    x = 428.29

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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.