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Finding the Fourth Proportional to 618.80, 928.34 and 436.55

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Solution

The fourth proportional to 618.80, 928.34 and 436.55 is: 654.92

Step by Step Solution

  1. Step 1: Write the proportion equation
    618.80 : 928.34 = 436.55 : x
  2. Step 2: Convert to fraction form
    618.80/928.34 = 436.55/x
  3. Step 3: Cross multiply
    618.80x = 928.34 × 436.55
  4. Step 4: Simplify right side
    618.80x = 405,261.64
  5. Step 5: Solve for x
    x = 405,261.64/618.80
  6. Step 6: Final answer
    x = 654.92

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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.