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Finding the Fourth Proportional to 491.80, 679.04 and 315.04

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Solution

The fourth proportional to 491.80, 679.04 and 315.04 is: 434.98

Step by Step Solution

  1. Step 1: Write the proportion equation
    491.80 : 679.04 = 315.04 : x
  2. Step 2: Convert to fraction form
    491.80/679.04 = 315.04/x
  3. Step 3: Cross multiply
    491.80x = 679.04 × 315.04
  4. Step 4: Simplify right side
    491.80x = 213,924.76
  5. Step 5: Solve for x
    x = 213,924.76/491.80
  6. Step 6: Final answer
    x = 434.98

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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.