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Finding the Fourth Proportional to 397.80, 549.09 and 315.27

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Solution

The fourth proportional to 397.80, 549.09 and 315.27 is: 435.17

Step by Step Solution

  1. Step 1: Write the proportion equation
    397.80 : 549.09 = 315.27 : x
  2. Step 2: Convert to fraction form
    397.80/549.09 = 315.27/x
  3. Step 3: Cross multiply
    397.80x = 549.09 × 315.27
  4. Step 4: Simplify right side
    397.80x = 173,111.60
  5. Step 5: Solve for x
    x = 173,111.60/397.80
  6. Step 6: Final answer
    x = 435.17

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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.