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Finding the Fourth Proportional to 659.85, 910.71 and 397.86

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Solution

The fourth proportional to 659.85, 910.71 and 397.86 is: 549.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    659.85 : 910.71 = 397.86 : x
  2. Step 2: Convert to fraction form
    659.85/910.71 = 397.86/x
  3. Step 3: Cross multiply
    659.85x = 910.71 × 397.86
  4. Step 4: Simplify right side
    659.85x = 362,335.08
  5. Step 5: Solve for x
    x = 362,335.08/659.85
  6. Step 6: Final answer
    x = 549.12

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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.