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Finding the Fourth Proportional to 485.51, 731.16 and 408.96

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Solution

The fourth proportional to 485.51, 731.16 and 408.96 is: 615.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    485.51 : 731.16 = 408.96 : x
  2. Step 2: Convert to fraction form
    485.51/731.16 = 408.96/x
  3. Step 3: Cross multiply
    485.51x = 731.16 × 408.96
  4. Step 4: Simplify right side
    485.51x = 299,015.19
  5. Step 5: Solve for x
    x = 299,015.19/485.51
  6. Step 6: Final answer
    x = 615.88

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.