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Finding the Fourth Proportional to 487.08, 670.68 and 485.64

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Solution

The fourth proportional to 487.08, 670.68 and 485.64 is: 668.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    487.08 : 670.68 = 485.64 : x
  2. Step 2: Convert to fraction form
    487.08/670.68 = 485.64/x
  3. Step 3: Cross multiply
    487.08x = 670.68 × 485.64
  4. Step 4: Simplify right side
    487.08x = 325,709.04
  5. Step 5: Solve for x
    x = 325,709.04/487.08
  6. Step 6: Final answer
    x = 668.70

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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.