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Finding the Fourth Proportional to 659.68, 909.12 and 485.12

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Solution

The fourth proportional to 659.68, 909.12 and 485.12 is: 668.55

Step by Step Solution

  1. Step 1: Write the proportion equation
    659.68 : 909.12 = 485.12 : x
  2. Step 2: Convert to fraction form
    659.68/909.12 = 485.12/x
  3. Step 3: Cross multiply
    659.68x = 909.12 × 485.12
  4. Step 4: Simplify right side
    659.68x = 441,032.29
  5. Step 5: Solve for x
    x = 441,032.29/659.68
  6. Step 6: Final answer
    x = 668.55

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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.