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Finding the Fourth Proportional to 639.36, 959.08 and 274.15

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Solution

The fourth proportional to 639.36, 959.08 and 274.15 is: 411.24

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.36 : 959.08 = 274.15 : x
  2. Step 2: Convert to fraction form
    639.36/959.08 = 274.15/x
  3. Step 3: Cross multiply
    639.36x = 959.08 × 274.15
  4. Step 4: Simplify right side
    639.36x = 262,931.78
  5. Step 5: Solve for x
    x = 262,931.78/639.36
  6. Step 6: Final answer
    x = 411.24

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Double scale
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Similar ratio
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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.