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Finding the Fourth Proportional to 538.20, 811.40 and 485.35

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Solution

The fourth proportional to 538.20, 811.40 and 485.35 is: 731.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    538.20 : 811.40 = 485.35 : x
  2. Step 2: Convert to fraction form
    538.20/811.40 = 485.35/x
  3. Step 3: Cross multiply
    538.20x = 811.40 × 485.35
  4. Step 4: Simplify right side
    538.20x = 393,808.53
  5. Step 5: Solve for x
    x = 393,808.53/538.20
  6. Step 6: Final answer
    x = 731.71

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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.