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Finding the Fourth Proportional to 538.80, 808.20 and 513.60

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Solution

The fourth proportional to 538.80, 808.20 and 513.60 is: 770.40

Step by Step Solution

  1. Step 1: Write the proportion equation
    538.80 : 808.20 = 513.60 : x
  2. Step 2: Convert to fraction form
    538.80/808.20 = 513.60/x
  3. Step 3: Cross multiply
    538.80x = 808.20 × 513.60
  4. Step 4: Simplify right side
    538.80x = 415,091.52
  5. Step 5: Solve for x
    x = 415,091.52/538.80
  6. Step 6: Final answer
    x = 770.40

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.