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Finding the Fourth Proportional to 668.40, 995.74 and 638.42

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Solution

The fourth proportional to 668.40, 995.74 and 638.42 is: 951.08

Step by Step Solution

  1. Step 1: Write the proportion equation
    668.40 : 995.74 = 638.42 : x
  2. Step 2: Convert to fraction form
    668.40/995.74 = 638.42/x
  3. Step 3: Cross multiply
    668.40x = 995.74 × 638.42
  4. Step 4: Simplify right side
    668.40x = 635,702.95
  5. Step 5: Solve for x
    x = 635,702.95/668.40
  6. Step 6: Final answer
    x = 951.08

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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.