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Finding the Fourth Proportional to 656.80, 985.38 and 520.30

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Solution

The fourth proportional to 656.80, 985.38 and 520.30 is: 780.59

Step by Step Solution

  1. Step 1: Write the proportion equation
    656.80 : 985.38 = 520.30 : x
  2. Step 2: Convert to fraction form
    656.80/985.38 = 520.30/x
  3. Step 3: Cross multiply
    656.80x = 985.38 × 520.30
  4. Step 4: Simplify right side
    656.80x = 512,693.21
  5. Step 5: Solve for x
    x = 512,693.21/656.80
  6. Step 6: Final answer
    x = 780.59

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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.